I reckon pipes are the hardest bloody thing to pick. Occasionally you see an engine/ pipe combo that really sings - but for us mere mortals, not that often. The trouble is you've got to buy lots of them to find that combo. We'v tried a number that were OK but the best combo we ever had was a Rody X/12 with the pipe of the same name. That pipe also worked decently well on older Nova engines, but not with the extra something.
The RD Turbo II pipe also displays that certain something and it was evident even when putting a few tanks through a tight new NSR in the street. Sam (son/driver) would be working the engine up through the rev range and suddenly it would come on song and get that nice howling sound.
OK, I'm getting a bit carried away here but what I'm trying to say is I think many "tuned" pipes seem to be tuned to an engine you haven't got.
Anyway this Turbo II rocks.
I would say, however, that the assembly quality was a little less than I expected. The header flange closest to the pipe seemed to have been assembled wrongly in two areas. The header tube leading in to that flange was off centre and I needed to relieve the inside of the tube in order to have it properly line up with the flange's hole. The second issue was that, when assembled, the stinger was pointing somewhat skywards. I drilled extra holes for the 3 springs in order to rotate the orientation and then needed to "correct" the ground clearence flat area under the flange.
I used a 1mm drill for this as well as doing some extra holes needed for the engine springs.
I'm not meaning to complain, just pointing out my experience. Given the good performance, I'd happily "correct" the next one.
And on the subject of weak pipes, I'd be struggling to put the RB X/12 in the tough catagory.