Sonic Turbo Equivalent Today

I think the sonic turbos were built off David Vizards design (or patent, I don't know if he patented it). I think if I wanted the best turbo style muffler, I would buy a walker/dynomax version.
I like the Flowmaster sound, but you have to have a big enough case with enough chambers to be quiet. Most that are too loud are too small/short/not enough baffles.