i have had RDZ pipes for the last year on my 392 cheetah. thought they ran good, but never had anything to compare them to. last dune trip, i put some shearers on there. didn't really notice much difference in performance; both seemed to pull up top about the same.
as far as quality, my RDZ i have never had a problem with, seem to be pretty solid. i was borrowing the shearers from a friend and after maybe a couple of hours of riding, they cracked and now need to be fixed. not sure of the history of the pipes, but i wasn't doing anything out of the ordinary with them on my bike. also, the rdz's are out each side and the shearers were both out the same side, so....
as far as fitment goes, the shearers fit waaaay better, hands down. the rdz's didn't fit bad, but the shearers were better.
i am selling my rdz's if anyone is interested. finally found some racer's edge pipes that i have been looking for since over a year ago. as soon as i get them cleaned up, i will post a fs ad, but let me know if you are interested.