schaake30:
Mufflers vs. cat-back:
Pros for mufflers only: stock exhaust tubing is stainless, cost for mufflers is significantly less than cat-back system, you can get exactly the mufflers you want.
Cons: Stock tubing is 2 1/4" dia. and will be restrictive if you add a supercharger, N2O, or generate >300 hp; sound may not be a 'rich' as bigger diameter tubing.
FWIW, I had UltraFlos welded into my stock cat-back before I installed the 'Packs and it was perfectly fine for me.
If you are sticking with a mainly stock motor and cash flow is tight, go with mufflers only. This will free up some cash sooner for a new x- or h-pipe (where you will get some good bang for your buck). If you are awash in moolah, go with the cat-back.
Hope this helps.