With regard to CM11 being "ever so flakey", I've definitely observed this, running CM11 on my Nexus 7 (2013, LTE) tablet. It works great, it really does, but after a couple weeks of uptime the network stopped working. A quick reboot and it was back in the game.

This is well worth it in return for the extra features that CM11 provides over stock Android (PrivacyGuard, trivial to root, etc.).