So, for a couple of months now I've been getting some inconsistent DTCs. The one that pops up most frequently is P0420 - catalyst inefficiency bank 1. There was a time it would pop up almost daily. Now I may get it once a week. To add to that, on occasion I will get both P0420 (bank 1) and P0430 (bank 2), like this past weekend. A month-or-so ago, I got a whole bunch of crazy codes in addition to those 2. The only one I remember had to do with driver headlight high voltage.

Ideas? I'm wondering if I truly have an exhaust issue (cats failing or O2 sensor something-or-other), or is there an electrical issue of some kind.