how do those razorcaps fly?

I've never used them but I've been seriously looking at them,about the only thing that turns me off though is thatthey want twice as much as a set of thunderheads, and there would have to be a significant advantage in those razorcaps over the thunderheads for me to justify dropping the extra cash on them...

I shoot 85gr thunderheads out of my compound and really like them and was(and still am) all set to get a 100gr set for my crossbow, however if those razorcaps are a superior enough broadhead I may go that route instead