I like my corsa system as it requires no cutting or welding and Corsa's chamber muffle design. Now with that said and the addition to down pipes on my car, it is quite loud. No drone, but very nasty sounding when cold. At WOT it gets quieter, must have something to do with more back pressure.
Now with all that said the stainless works exhaust seems to be of good value, I think Borla discontinued there system, and magna flow I have read they use a stainless steal that rusts.