Foximus,
I have a 94 Superjet with all the standard mods (b-pipe, 175psi, msd, 3° static advance, carbon tech, wet wolf cone, worx 201, blah, blah, blah).
My current impeller is a Skat 9/17 Standard. I have tried the Solas Concord 13/17, 12/17, 12/15 (something like that...trust me a bunch of different bends), all cutback 3mm and all had an off idle dead spot, but great overall hookup. Not as fun as my Skat 9/17 Standard IMHO.
I just tried (yesterday) my friends Skat 12/17 Swirl cutback 3mm and it is a good prop. No off idle dead spots good hook up (maybe not quite as good hook-up as the Concord but no dead spots).
However, I don't really think I had any extra bottom end or top end from the Skat Swirl 12/17 -3mm compared to my Skat Standard 9/17. The Swirl does have a little better hook up and is harder to break free......but honestly I like being able to break free.
So I guess what I am saying is apply the $250.00 you were going to spend on a prop and get a Factory B-Pipe. If anything repitch the 10/18 to a 9/17 and you are set. If you have extra cash burning a hole in your pocket and feel you need the little bit of extra hook-up the Swirl provides...then drop the coin.
The old school Skat props are awesome props. Skat Trak got it right the first time. I keep trying to replace my 9/17, I just can't find anything significantly better.
JC