I've been using it since the aosp v4.1.1 v1 dropped. Extremely awesome. I did have a couple issues, all of which have been extinguished except one. The issues I know have been addressed are bluetooth cutting out from 2+feet and beyond, GPS lock rate, and MMS 160 char. The one I have yet to figure out (whether it works on ANY JB or not) and is MAJOR for me. I cannot get it to sync my exchange work email. I set it up as necessary, using the same credentials i've used a million times before. It shows set up successful. Then when I fire up the email app, it sits there "waiting to sync" and never gets past this.
Looking into other JB roms to see if they're having the same issues. As much as I love this rom I may need to evaluate an other rom. I *NEED* my exchange email, considering I'm the network specialist at my place of employment. Not having access to email and calendar is not good.