[Asus Transformer TF701] hitmancho:
My problems with formatting were rather weird. I started by formatting my caches, which is always an issue with /cache not wanting to mount properly when formatting into ext4. What I always do is: format /cache into ext3, ext2, fat, and the back to ext4 where it finally works. After that I wiped /system with no issues, as well as /data. After that I tried the Format Data option from the Wipe menu, which wipes internal memory plus /data (?) but it just hanged and then it gave me an error and told me /data may not be mountable. Sure enough, after rebooting my recovery, /data had to be reformatted into ext3 and the back into ext4 to be mountable and usable. After that my internals were clean (including my internal storage) with the only space taken up by each partition being some sort of "backup size". I then proceeded to install your ROM but it took a while and then it gave me an error with the /system mountspace being busy. I realized I had accidentally left /system mounted in the recovery, so what I did was I reformatted /system back into ext3 then into ext4 after rebooting the recovery so it could be mountable. Then I just wiped all my partitions (caches, /system and /data) to make sure the ext4 command was working properly and indeed it was. I checked up on my internal storage and saw it was empty, save for the TWRP dir where the recovery keeps its settings. I made sure I didn't leave /system mounted and then I flashed the ROM again. It still took a while to flash (some minutes) but it was successful. I then flashed SuperSU which was fast, then I flashed nano GApps, which took a while as well, after which I wiped dalvik and /cache for good measure again (they ran fine, without issues). After that I restarted the tablet and the ROM started booting. It took a couple of minutes, like it says in the guide, then it started optimizing apps, which was surprisingly fast (there were 47 apps, if I'm not mistaken). Then the ROM started and I did the setup wizard, without restoring anything AT ALL, just logging in with my account. I noticed that it was quite laggy on that menu, but I guessed it was to be expected. After that I started playing around with everything (interface, etc.) and I noticed my screen flickering like with auto brightness left on. I had reduced my brightness to the minimum, seeing as it was nighttime, so I decided to raise it a little bit, since it was actually darker than CM12.1 (adaptive brightness was never on the whole time, I tried switching it back on to see if something would "reset" and then turning it off, it didn't help). My brightness kept moving around a few levels on its own, not matter how I set it up. I decided to use the tablet for a little bit, leave the ROM to settle in before installing anything. It kept doing a strange stutter on most of its menus, and some apps took 5+ seconds to open. I decided to let it do its thing and after installing an app or two I rebooted it. Note, I didn't have any media on my tablet whatsoever, considering it was wiped all the way. I installed a few apps, decided to reboot the tablet. It booted fast enough but the interface and app lag persisted. After that, for the heck of it, I decided to install Xposed framework (the one for Marshmallow, ofc). It worked without a hitch but the moment I decided to install a module and then start it and reset the tablet it just ended up in a bootloop. I gave up after that and decided to restore my previous installation. It went without any problems and it ran as before, but at least I cleaned up all my internal storage's empty dirs and whatnot :D.

How would you recommend I wipe and install the ROM, seeing as how I'm the only one having these issues? It was probably caused by all that wiping and failing to mount shenanigans (I sure hope my flash storage isn't dying or anything). I might try the ROM back again in some days, since I have work to do now and I don't have time to mess with it for too long, and I might even need it. I really want to try this ROM, since it's MM and has all these functions that really make life easier, but something is going wrong on my end :D.