[Galaxy S6 Edge Q&A, Help & Troubleshooting] Emieltes:
This is the build.prop in my S6 G920F (no edge) on android 5.0.2;

# begin build properties

# autogenerated by buildinfo.sh

ro.build.id=LRX22G

ro.build.display.id=LRX22G.G920FXXU1AOE3

ro.build.version.incremental=G920FXXU1AOE3

ro.build.version.sdk=21

ro.build.version.codename=REL

ro.build.version.all_codenames=REL

ro.build.version.release=5.0.2

ro.build.date=Wed May 6 17:07:29 KST 2015

ro.build.date.utc=1430899649

ro.build.type=user

ro.build.user=dpi

ro.build.host=SWDD5819

ro.build.tags=release-keys

ro.product.model=SM-G920F

ro.product.brand=samsung

ro.product.name=zerofltexx

ro.product.device=zeroflte

ro.product.board=universal7420

# ro.product.cpu.abi and ro.product.cpu.abi2 are obsolete,

# use ro.product.cpu.abilist instead.

ro.product.cpu.abi=arm64-v8a

ro.product.cpu.abilist=arm64-v8a,armeabi-v7a,armeabi

ro.product.cpu.abilist32=armeabi-v7a,armeabi

ro.product.cpu.abilist64=arm64-v8a

ro.product.manufacturer=samsung

ro.product.locale.language=en

ro.product.locale.region=GB

ro.wifi.channels=

ro.board.platform=exynos5

# ro.build.product is obsolete; use ro.product.device

ro.build.product=zeroflte

# Do not try to parse description, fingerprint, or thumbprint

ro.build.description=zerofltexx-user 5.0.2 LRX22G G920FXXU1AOE3 release-keys

ro.build.fingerprint=samsung/zerofltexx/zeroflte:5.0.2/LRX22G/G920FXXU1AOE3:user/release-keys

ro.build.characteristics=phone

# Samsung Specific Properties

ro.build.PDA=G920FXXU1AOE3

ro.build.hidden_ver=G920FXXU1AOE3

ro.config.rm_preload_enabled=0

ro.build.changelist=4497415

ro.product_ship=true

ro.chipname=exynos7420

persist.sys.storage_preload=1

# end build properties

#

# HWUI_BUILD_PROPERTIES

#

ro.hwui.texture_cache_size=88

ro.hwui.layer_cache_size=58

ro.hwui.path_cache_size=16

ro.hwui.shape_cache_size=4

ro.hwui.gradient_cache_size=2

ro.hwui.drop_shadow_cache_size=8

ro.hwui.r_buffer_cache_size=4

ro.hwui.text_small_cache_width=2048

ro.hwui.text_small_cache_height=2048

ro.hwui.text_large_cache_width=4096

ro.hwui.text_large_cache_height=4096

#

# from device/samsung/zeroflte/system.prop

#

#

# system.prop for universal7420

#

rild.libpath=/system/lib64/libsec-ril.so

rild.libargs=-d /dev/ttyS0

ro.sf.lcd_density=640

# RIL team modification

# netmgrd should be false in EVO-RIL model

ro.use_data_netmgrd=false

# RIL team modification

# qos will temporary false while supporting qos in EVO-RIL.

persist.data.netmgrd.qos.enable=false

ro.arch=exynos7420

persist.demo.hdmirotationlock=false

ro.zygote.disable_gl_preload=1

ro.sf.lcd_density=640

# GSM should be 0

telephony.lteOnCdmaDevice=0

# Start in gsm mode

ro.telephony.default_network=9

# Multimedia property for Smart View

media.enable-commonsource=true

# DHA property

ro.config.dha_cached_max=15

ro.config.dha_cached_min=4

ro.config.dha_empty_max=36

ro.config.dha_empty_min=9

ro.config.dha_empty_init=36

ro.config.dha_lmk_scale=0.990

ro.config.dha_th_rate=1.83

ro.config.sdha_apps_bg_max=70

ro.config.sdha_apps_bg_min=8

ro.config.dha_ils_enable=true

ro.config.dha_ils_dyna_lmk=true

ro.config.dha_ils_rate=1.5

#Some Tweaks

persist.cust.tel.eons=1

ro.config.hw_fast_dormancy=1

debug.performance.tuning=1

debug.composition.type=gpu

ro.config.vc_call_steps=20

ro.ril.enable.amr.wideband=1

ro.ril.disable.power.collapse=1

pm.sleep_mode=1

debug.enabletr=true

debug.overlayui.enable=1

debug.qctwa.preservebuf=1

hw3d.force=1

ro.config.disable.hw_accel=false

ro.fb.mode=1

ro.sf.compbypass.enable=0

ro.vold.umsdirtyratio=20

persist.sys.ui.hw=1

ring.delay=0

ro.telephony.call_ring.delay=0

ro.lge.proximity.delay=15

mot.proximity.delay=15

power.saving.mode=1

proximity_incall=enable

ro.config.hw_quickpoweron=true

ro.config.hw_power_saving=true

ro.media.enc.jpeg.quality=100

ro.config.nocheckin=1

ro.kernel.android.checkjni=0

ro.kernel.checkjni=0

ro.mot.eri.losalert.delay=1000

ro.config.hw_quickpoweron=true

debugtool.anrhistory=0

profiler.debugmonitor=false

profiler.launch=false

profiler.hung.dumpdobugreport=false

profiler.force_disable_ulog=1

profiler.force_disable_err_rpt=1

af.resampler.quality=255

# 3g signal tweaks

ro.ril.hsxpa=3

ro.ril.gprsclass=10

ro.ril.hep=1

ro.ril.enable.dtm=1

ro.ril.hsdpa.category=12

ro.ril.enable.a53=1

ro.ril.enable.3g.prefix=1

ro.ril.htcmaskw1.bitmask=4294967295

ro.ril.htcmaskw1=14449

ro.ril.hsupa.category=7

ro.ril.hsdpa.category=10

ro.ril.enable.a52=1

ro.ril.set.mtu1472=1

persist.cust.tel.eons=1

ro.config.hw_fast_dormancy=1

persist.data_netmgrd_mtu=1482

persist.data_netmgrd_nint=8

ro.use_data_netmgrd=true

ro.ril.enable.dtm=1

ro.ril.def.agps.mode=2

ro.ril.def.agps.feature=1

ro.ril.enable.gea3=1

ro.ril.enable.fd.plmn.prefix=23402,23410,23411

# GOOGLE DNS

net.dns1=8.8.8.8

net.dns2=8.8.4.4

net.rmnet0.dns1=8.8.8.8

net.rmnet0.dns2=8.8.4.4

net.ppp0.dns1=8.8.8.8

net.ppp0.dns2=8.8.4.4

net.wlan0.dns1=8.8.8.8

net.wlan0.dns2=8.8.4.4

net.eth0.dns1=8.8.8.8

net.eth0.dns2=8.8.4.4

net.gprs.dns1=8.8.8.8

net.gprs.dns2=8.8.4.4

# Better internet browsing & download speed

net.tcp.buffersize.default=4096,87380,256960,4096, 16384,256960

net.tcp.buffersize.wifi=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.umts=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.gprs=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.edge=4096,87380,256960,4096,163 84,256960

net.tcp.buffersize.hspa=6144,87380,524288,6144,163 84,262144

net.tcp.buffersize.lte=524288,1048576,2097152,5242 88,1048576,2097152

net.tcp.buffersize.hsdpa=6144,87380,1048576,6144,8 7380,1048576

net.tcp.buffersize.evdo_b=6144,87380,1048576,6144, 87380,1048576

#Block redirect

sysctl -w net.ipv4.conf.all.accept_redirects=0;

sysctl -w net.ipv4.conf.default.accept_redirects=0;

sysctl -w net.ipv4.conf.all.secure_redirects=0;

sysctl -w net.ipv4.conf.default.secure_redirects=0;

#

#Wireless and TCP4 Tweaks

wifi.supplicant_scan_interval=300

net.ipv4.ip_no_pmtu_disc=0

net.ipv4.route.flush=1

net.ipv4.tcp_ecn=0

net.ipv4.tcp_fack=1

net.ipv4.tcp_rfc1337=1

net.ipv4.tcp_sack=1

net.ipv4.tcp_timestamps=1

net.ipv4.tcp_rmem=4096 39000 187000

net.ipv4.tcp_wmem=4096 39000 187000

net.ipv4.tcp_mem=187000 187000 187000

net.ipv4.tcp_no_metrics_save=1

net.ipv4.tcp_moderate_rcvbuf=1

net.ipv4.tcp_window_scaling=1

#

# VQG - User Agent Header for Video-Streaming Client

net.streaming.rtsp.uaprof=http://wap.samsungmobile.com/uaprof/

# Multimedia property for Camcorder Recording

media.sfrec.adj_frames=2

# System property for storage_preload

persist.sys.storage_preload=1

#

# ADDITIONAL_BUILD_PROPERTIES

#

ro.config.tima=1

ro.config.timaversion=3.0

ro.config.ringtone=Over_the_Horizon.ogg

ro.config.notification_sound=Skyline.ogg

ro.config.alarm_alert=Morning_Flower.ogg

ro.config.media_sound=Media_preview_Touch_the_light.ogg

dalvik.vm.heapstartsize=8m

dalvik.vm.heapgrowthlimit=256m

dalvik.vm.heapsize=512m

dalvik.vm.heaptargetutilization=0.75

dalvik.vm.heapminfree=2m

dalvik.vm.heapmaxfree=8m

ro.opengles.version=196609

ro.sf.lcd_density=480

debug.hwc.nodirtyregion=0

debug.hwc.winupdate=1

drm.service.enabled=true

ro.hdcp2.rx=tz

ro.secwvk=220

ro.securestorage.support=true

ro.security.gfservice.version=0.9.2

ro.security.gfservice.whitelist=true

ro.security.gfservice.unload=false

ro.build.scafe=capuccino

ro.build.scafe.size=short

ro.build.scafe.shot=single

ro.build.scafe.cream=white

ro.sec.fle.encryption=false

ro.im.param.offset=7341648

ro.me.param.offset=7341728

ro.sn.param.offset=7341808

ro.pr.param.offset=7341888

ro.sku.param.offset=7341968

security.mdpp=None

ro.security.mdpp.ver=2.0

ro.security.mdpp.release=2

ro.security.vpnpp.ver=1.4

ro.security.vpnpp.release=4.1

security.mdpp.result=None

ro.error.receiver.default=com.samsung.receiver.error

config.disable_atlas=true

ro.security.mdpp.ux=Enabled

ro.security.reactive.active=2

keyguard.no_require_sim=true

ro.com.android.dateformat=MM-dd-yyyy

ro.carrier=unknown

ro.com.google.clientidbase=android-samsung

ro.security.icd.flagmode=multi

ro.adb.qemud=1

ro.setupwizard.mode=DISABLED

ro.com.google.gmsversion=5.0_r2

persist.sys.dalvik.vm.lib.2=libart.so

ro.build.selinux=1

dalvik.vm.isa.arm64.features=default

dalvik.vm.isa.arm.features=div

ro.config.knox=v30

ro.kernel.qemu=0

dalvik.vm.dexopt-flags=m=y

net.bt.name=Android

dalvik.vm.stack-trace-file=/data/anr/traces.txt

ro.build.version.sdl=2101

I'm still testing alot of the settings but it seems that i get way better signal reception now (H+ in places where I only had G signal at first) and the multitasking is much improved. Some of tweaks are probably useless and I'm still trying out which ones. I hope this is usefull to you.