[Sony Cross-Device General] theplagueisback:
I think it didn't work for me, it didn't reboot my phone automatically and upon manually rebooting it there are no visible instructions on how to start the second boot loader, here's the installer output:

==============================================
= =
= PhilZ Touch, CWM and TWRP Dual Recovery =
= Maintained by [NUT] =
= =
= For Many Sony Xperia Devices! =
= =
==============================================

1. Installation on ROM rooted with SuperSU
2. Installation on ROM rooted with SuperUser
3. Installation on unrooted ROM using the TowelRoot method
4. Install ADB drivers to windows
5. Exit

Please choose install action.
[1,2,3,4,5]?3
* daemon not running. starting it now on port 5037 *
* daemon started successfully *

=============================================
Waiting for Device, connect USB cable now...
=============================================
Device found!

=============================================
Getting ro.build.product
=============================================
Device model is C6833
Firmware is 14.4.A.0.108

=============================================
Step2 : Sending the recovery files.
=============================================
mkdir failed for /data/local/tmp/recovery, File exists
14 KB/s (29 bytes in 0.002s)
3847 KB/s (15757 bytes in 0.003s)
244 KB/s (501 bytes in 0.002s)
3856 KB/s (11842 bytes in 0.002s)
4624 KB/s (56834 bytes in 0.012s)
1002 KB/s (3082 bytes in 0.003s)
125 KB/s (385 bytes in 0.003s)
4902 KB/s (657704 bytes in 0.131s)
4884 KB/s (3171075 bytes in 0.634s)
5301 KB/s (2329218 bytes in 0.429s)
5437 KB/s (1876491 bytes in 0.337s)
2893 KB/s (8889 bytes in 0.003s)

=============================================
Step3 : Setup of dual recovery.
=============================================
=============================================
Attempting to get root access for installation using TowelRoot now.

NOTE: this only works on certain ROM/Kernel versions!

If it fails, please check the development thread (Post #2) on XDA for more detai
ls.

REMEMBER THIS:

XZDualRecovery does NOT install any superuser app!!

You can use one of the recoveries to root your device.
=============================================

=============================================
Sending files
=============================================
767 KB/s (1572 bytes in 0.002s)
3317 KB/s (13592 bytes in 0.004s)
4940 KB/s (197320 bytes in 0.039s)
3092 KB/s (9496 bytes in 0.002s)
3336 KB/s (13672 bytes in 0.004s)
Copying kernel module...
4208 KB/s (34473 bytes in 0.008s)
373 KB/s (765 bytes in 0.001s)
4427 KB/s (13592 bytes in 0.002s)
Kernel version is 3.4.0-perf-g0109737
Version does not match 3.4.0-perf-ge4322cd, needs patching...
1+0 records in
0+1 records out
19 bytes transferred in 0.001 secs (19000 bytes/sec)
Kernel module patched.

modulecrcpatch (by zxz0O0)

module_layout: match
__aeabi_unwind_cpp_pr1: match
kallsyms_lookup_name: not found
printk: not found
mem_text_write_kernel_word: not found
__aeabi_unwind_cpp_pr0: match
successfully patched

=============================================
Installing using zxz0O0's towelzxperia
(using geohot's towelroot library)
=============================================

towelzxperia (by zxz0O0)
thanks to geohot for libexploit

doing the magic
creating vm (loljavasucks)
libdvm opened (loljavasucks)
cleaning up
/system/bin/sh: /system/xbin/busybox: not found

=============================================
Installation finished. Enjoy the recoveries!
=============================================

Press any key to continue . . .

---------- Post added at 11:07 AM ---------- Previous post was at 11:04 AM ----------

Never mind, had chosen the wrong option, #1 worked:

==============================================
= =
= PhilZ Touch, CWM and TWRP Dual Recovery =
= Maintained by [NUT] =
= =
= For Many Sony Xperia Devices! =
= =
==============================================

1. Installation on ROM rooted with SuperSU
2. Installation on ROM rooted with SuperUser
3. Installation on unrooted ROM using the TowelRoot method
4. Install ADB drivers to windows
5. Exit

Please choose install action.
[1,2,3,4,5]?1
* daemon not running. starting it now on port 5037 *
* daemon started successfully *

=============================================
Waiting for Device, connect USB cable now...
=============================================
Device found!

=============================================
Getting ro.build.product
=============================================
Device model is C6833
Firmware is 14.4.A.0.108

=============================================
Step2 : Sending the recovery files.
=============================================
mkdir failed for /data/local/tmp/recovery, File exists
7 KB/s (29 bytes in 0.004s)
2198 KB/s (15757 bytes in 0.007s)
163 KB/s (501 bytes in 0.002s)
1927 KB/s (11842 bytes in 0.006s)
2921 KB/s (56834 bytes in 0.019s)
752 KB/s (3082 bytes in 0.003s)
93 KB/s (385 bytes in 0.004s)
2780 KB/s (657704 bytes in 0.231s)
2830 KB/s (3171075 bytes in 1.094s)
2773 KB/s (2329218 bytes in 0.820s)
3237 KB/s (1876491 bytes in 0.566s)
1446 KB/s (8889 bytes in 0.006s)

=============================================
Step3 : Setup of dual recovery.
=============================================
Look at your device and grant supersu access!
Press any key to continue AFTER granting root access.
-rwxr-xr-x 1 shell shell 657704 Jan 1 16:16 /data/local/tmp/recover
y/busybox
Press any key to continue . . .

##########################################################
#
# Installing XZDR version 2.7.159 BETA
#
#####

Temporarily disabling the RIC service, remount rootfs and /system writable to al
low installation.
insmod: init_module '/data/local/tmp/wp_mod.ko' failed (File exists)
Copy recovery files to system.
Rename stock mr
Copy mr wrapper script to system.
Rename stock chargemon
Copy chargemon script to system.
Copy dualrecovery.sh to system.
Copy rickiller.sh to system.
Installing NDRUtils to system.
Copy disableric to system.
Creating /system/.XZDualRecovery to store a backup copy of busybox.
Copy busybox to system.
Trying to find and update the gpio-keys event node.
Found and will be using /dev/input/event5!
Trying to find and update the power key event node.
Found and will be monitoring /dev/input/event4!
Speeding up backups.
Make sure firstboot goes to recovery.

=============================================
DEVICE WILL NOW TRY A DATA SAFE REBOOT!
=============================================

=============================================
Your installation has already cleaned up after
itself if you see the install.bat/install.sh exit.
=============================================

=============================================
Installation finished. Enjoy the recoveries!
=============================================

Press any key to continue . . .

---------- Post added at 11:09 AM ---------- Previous post was at 11:07 AM ----------

B-E-A-utilful, I've managed to make the SD Card writable now...

Thanks a lot for the help!