halocon

i was at performance bike today and i saw that the speedplay x5's were on sale for 70 bucks and i was thinking of getting a pair. does anyone have experience with the x5's? the look pp357's gave me a tough time. locking in was hard and disengaging was hard. and i got sore knees from them after a bit of riding. the x5's seem promising with their claims on the website about how easy it is to disengage and lock in. and the float that prevents sore knees sounds pretty tempting. can anyone shed some light about their experience with the x5's or speedplay x series pedals in general? i need lots of details! thx!