He's right about the exhaust clamps. Whatever system you get use band clamps like shown in the link above. The exhaust clamps crimp the overlapping exhaust clamp/exhaust pipe together due to the force on the round U type bolt against the exhaust pipes. Once they are torqued down, even if you loosen the clamp the pipes, are crimped together. I fought my exhaust trying to get it off because of those clamps. Take's a sawzall to cut the old exhaust off.You might want to look at this... ...
http://www.grpipes.com/powerflow.asp
the "other" clamp is the one you get with a MBRP kit. The accu-clamp is worth a few more bucks