Yea I've had the x37,x47,and x47r. X47r spooled slower but who knows it could just be my tuner. In the UK people seem to have success with it. Felt stronger on top.
I never dynoed my x47, but I dynoed my x47r and made 290whp 300tq.
That's with -x47r, fbo, MAP charge pipes, exhaust manifold, e30, 60/40 meth.
In my opinion I felt like there should of been more power to it, I mean I got tuned in just under 6 revisions lol so again who knows what ots capable of.