I've had them on 2 different sleds and they work great. I'm not sure performance wise.. I don't think they give more hp's like they say they do.. however I dont think v force's do either. But if you think about it, they are made of aluminum and you'll never have to worry about delaminating boots..
Just my .02
This is exactly why I used them on my rev that I did a 700 top end swap on...Throttle response was more crisp...but idk about the horsepower numbers that are claimed...