I've got my orignal knee bars and really like them. Although I have bought a pair of the elite straps that pinhead makes, (see mod's thread) as they give you a bit more security.
I tried my friends calf cuffs an didn't get on with them. They just felt to loose an my legs were all over the place. However, they wern't set up for me, so that maybe why.. I'd like to try them again with the right set up for me as they do look a lot more comfortable..
But as everyone says it's personal prefrance. I suppose £29.99 isn't a lot of money so you could just buy a pair an if you don't get on with them i'm sure some one on here will buy them from you!
JJ