I may be one of the few, I honestly dont know how many people use him, but I didn't have any luck with shafiroff. A few people i know call him
shaftiroff, but I wish you lots of luck with them, maybe your experience will be better.
I drove for a guy that bought a motor from him, Scott sold him a dyno mule for full price. This rod came out of the oil pan at 1000' (around 130 mph)

That was the worst ride of my life... since then I wont recommend them, however, like i said before, I wish you the best with it.