In reply to jkarran:
> Belaymaster would be a PITA. Jon's suggestion of an oval is a better one if this still concerns you.
To provide an alternative perspective - I find my Belaymaster no hassle at all. I used to have an old one which I decided was a bit battered and needed replacing, and thought about buying something else, but it really doesn't bother me at all. So now I have a nice I-beam one.
Takes maybe a quarter of a second to do up the clip, and as well as avoiding cross-loading, it makes it really obvious if you've forgotten to do it up. Only time it is a hassle is (a) if you need to use the crab for something other than belaying (b) if you want to lock off your belay plate, neither of which are exactly common.