I read a lot through the past psot in regards to cat back systems. I am not ready to shell out the money for the high-end systems like a Corsa and I am not going to build a tru dual system.
I see that the MagnaFlow and the DynoMax Ultra Flo systems get a lot of nods here.
Considering that the DynoMax system is exactly $100 less than the MagnaFlow, i am torn.
Please tell me about the sound and resonance of these two systems to help me make a decision. MagnaFlow psots nice power gains on the 5.3 too.

Anyway, please help!!!

 

Well I have/had both at one point. I used a Dynomax SuperTurbo (similar to the Ultra Flo) on my ol' 99 Z71 and loved it. The sound was deep, mellow, and pretty quiet at cruise. Decently loud at a WOT run. That was a medium sized cased one and just had a very cool tone. The Magnaflow I run now is a HUGE cased one and pretty darn quiet, but that is what I wanted. It still has a tone similar to the Dynomax just a bit quieter.

A good general rule of thumb is the larger the case the quieter the sound. Straight through mufflers also tend to drone very little or not at all on a freeway cruise.