I dont like them. They dont give you much power. They say 9-12 rwhp, but I saw a test recently where they didnt even put the belt on for a dyno run. Guess what, with no belt at all, they picked up 8 rwhp.
A friend of mine had those.....and it ended ugly. They didnt seal well on the front crank seal and it started leaking. I made him put the stock pulleys on when we put the KB on his car. The leak stopped. The crank pulley was also not true. It had a noticable wobble. If you had bought the Steeda ones....thats another story. I have yet to see a set of them made badly, but then again, we are back to the same "what performance am I actually getting for the money".
FWIW, the Steeda pulleys were designed by Ford, more or less. They're more expensive, but I wouldn't put anything less on my car when it comes to stuff like that.
Also, pulleys have been proven to gain .1 and 1 mph in the 1/4 mile on 2-valve cars.