[G4 Q&A, Help & Troubleshooting] MickyFoley:
OnePlus 2:

Pro:

• Battery is superior with GPS (As good as no loss in battery using Maps)

• Fingerprint (Although it's a bit picky sometimes)

• 1080p gives overall a better battery duration

• Worthy look & feel

• Lord Boeffla is officially supporting it (He should be really well known)

• A near vanilla android feeling

• 4GB of RAM (At least for the 64GB variant)

• Price for features and hardware

Con:

• No fingerprint for AOSP

• Laser Auto Focus only worked with a specific build of CM12.1 (AuxXxilium with VISION)

• No real professional ROMs from OnePlus themselves (Yes, the ROMs have major bugs, but beside they try to fix them, it's a mess...)

• Optical Image Stabilization isn't really working, even with LAF

• No sources for devs except the kernel itself

• USB Type C (USB 2.0 variant, but that's not the problem. The problem is: You really have troubles to find good cables & having everytime an own cable with you)

LG G4:

Pro:

• QHD-display

• Expandable memory

• Changeable battery

• codeworkx (A legendary legend is doing the major development of CM13 for us! If you don't know him: Google him. I'd call him godlike and will mention him in one sentence with chainfire!)

• googy_anas (A famous kernel-dev is giving us a neat kernel, formerly doing more than awesome stuff for Samsung devices!)

• AntaresOne will come (The legendary CM-Optimized major developer of Samsung Galaxy S4 - maybe also with JDCTeam & googy_anas will probably help too. I asked for it :). Source: https://plus.google.com/u/0/+MattiaDAlleva/posts/MNN2L1KRqaL & kernel thread from googy_anas)

• One of the best cameras out until now with stunning ability to shoot photos and make videos

• OIS is working seamless and giving you a perfect shot everytime you need it

• Manual camera support (God, this feature kicks ass, believe me!)

• Already Marshmallow

• A more than a well done stock-android from LG (Yes, I simply love the features)

Con:

• If you don't have a supported device, you won't have the benefits of freedom. Why? Because there are several devices of the G4, unlocking the bootloader isn't possible & so: No chance of doing stuff for many users.

• Changing DPI is a mess, if you'll go smaller than 538DPI. Stock apps will crash immediately (To be honest: They should simply ship it with 540DPI - display is 538DPI. 640 (Stock) is way too much, because you really feel, it's a device for shortsighted people only)

• Installing Xposed is a pain, if you don't install deodexed system apps (Android 6.0.x). If you don't, your phone simply won't boot and will in worst case overheat

• No real con: Max. 32GB versions out - wouldn't have hurt to provide also a 64GB variant

• No real con: Wireless charging needs a small hack to the back cover. Pins are there and there are covers out from LG (I guess), supporting it. The cover also has enough place (proven!). IDK why they missed this part so badly

I have both devices and have to confess, I didn't touch my OnePlus 2 for a few months. I don't miss fingerprint that much, but would have - for sure - granted to get faster access than pressing the button itself. I'm simply satisfied about my H815, unlocked bootloader, TWRP and so on. The leatherback is a welcomed feature, so it feels worthy and won't get slippery (Have the black one). If you want me to pick a winner: LG for sure. But simply, because OnePlus missed the chance to give out the sources to the devs. The OnePlus One was a great phone, but the OPT isn't getting the needed attention because of the lack of sources. They shot themselves into their knees, because a) they had their invitation-system for too long, so most devs simply went over to other devices an b) like I said, the lack of support from OnePlus themselves.