fg: lolpetewtf has a great answer w/an awesome link
. The stock HU leaves a lot to be desired. You most likely will want to replace the speakers as well if you decided to replace the HU.
Because of where I live, I opted to just exchange my speakers, keep my stock HU & picked up something like this to play my Ipod with: Quadratec Exclusive JW-AUX-IN - Auxiliary Audio Input Adapter Kit for 97-06 Jeep® Wrangler TJ & Unlimited - Quadratec
. Mine is slightly different but works great (Zero interference), I'm happy
. It's all about what you want & what your goal is.