They are a very good muffler for the price.
I run them on my daily driver 71 Elky with a 325HP 350.
I really like the way they sound, had them on for 2 years now and they have seen lots of 6500RPM runs thru them without them blowing out.
They still sound good, Im going to put them on the Blazer when I clean things up.
For the $$$, they're hard to beat