If you jumped on board 4.2 in the first week or two after it was released, you may have run into some issues.
All of the bugs have since been worked out. If you install a 4.2 ROM now and are still having issues, it's most likely user error.
Most, if not all ROM's, are stable now and are only differentiated by the features.
I have been running Euroskank's AOKP for quite a while now with no issues. You may have to try out different kernels to find one that you and your phone likes, though.
Also, don't forget to flash the latest recovery before doing any backups. Just do it.