[Mi 3 Original Android Development] Mr Rainman:
Initial testing:

First thing I encountered when flashing through TWRP (2.8.7.0) was the excact same "bug" that Ivan's ROM has: even with repartitioned system, after flashing the ROM, recovery seems to think I haven't repartitioned it yet, thus not leaving enough space for Gapps (slim gapps mini version). Followed the usual workaround:

install ROM>take backup of system and boot>install repartition zip> restore system.

After installing Gapps, I booted it up and everything went as excpected, meaning there were no hiccups, boot seemed even quite fast for a first one and left my phone running quite cool, much unlike some other ROMs.

The bugs others mentioned were all tere:

Screen-on during call (easily fixable by simply manually locking the screen with power button). IMHO it's also greatly outweighed by the fact that ambient display works.

NFC isn't working either (doesn't really matter to me, not using it). It was off by default and after toggling it, it kind of went gray and disabled all the NFC related options (see attachments). Stayed exactly the same after a reboot. If i was to clear my data for some reason, I'll promise taking a logcat while toggling the NFC on for the first time if I remember to do so. Suggest the same for everyone else.

Despite 4 reboots I made, I haven't encountered no-SIM bug yet, meaning it's rare enough to not be disturbing. As confirmed by OP though, it's still there as the fix was only partial.

Adaptive brightness is working for me, unlike someone else who said it doesn't. It is a bit more dim than I'd like though... Maybe change the default brightness a bit higher? (then again, I can ofcourse just move the slider a bit higer though)

On performance, I'd say it's 8.5/10, meaning that it has a little bit of room to improve. The ROM runs smooth, even very smooth but I feel as if it could do just a little better (for example, try scrolling through settings, its still smooth but I don't get that 60fps buttery feeling, then again, I'm not sure, might just be me...). Battery life seems somewhere inbetween Ivan's and Omnirom 13/07 version. Haven't noticed any battery drain while idle yet, probably a good sign. Onscreen time seems just a liiiiitle bit worse than Ivan's but that might just be the result of it being just flashed, I'll give it time to settle down and see what happens then.

Overall, it seems smooth and stable enough for me and considering the soon-arriving nightlies, I'll probably be keeping it as my daily driver. If you rely heavily on NFC or desparately want to use the powerbutton-ends-call feature though, then I'd suggest you wait a little bit before installing it.

My gratitude to OP for this amazing project, hope this journey goes on for a long time :good::good::good:

Edit: Had to uninstal NFCservice completely using titanium backup. After I did what I mentioned before, phone just didn't go into sleep and nfcservice was holding a constant wakelock. If that doesn't fix it, I'll report back later. Damn, forgot to take a logcat, guess it's too late now...

Edit2 :After deleting everything NFC related from /system, things seem to have settled down. Unless you're testing and actually want to be poking around I suggest you stay the hell away from that NFC toggle.