I have the Park PCS-9, and its fine for my home use. I set the clamp angle to grab seatposts (all of mine are alloy) and have never had any trouble. Yes, its not quick, but it works fine for my needs! I got it years ago for just over $100 on sale. Good deal at the time.
However, for $40-50 more, get the PCS-10 and have a better clamp that will be easier to use.