The weight?I know I'm late to the party but have to throw in my 2 cents. Unlike the McGizmo clips that I no longer use both because of weight and their tendency to come unclipped in my pocket, I've used one of these for years and never had it accidentally come unclipped plus they're very light. And at $1.00 each the price is hard to beat.
http://www.photonlight.com/Quick-Release-Keyring-Silver-p/qrclip-s.htm
The weight?
I don't know how you could think the upper right clip is lighter than the lower right clip. As for them coming undone, I've been using these things for many years and I've never had a single one come undone. I'm only using that photon style one because I haven't gotten around to ordering more of the mcgizmo clips. If you guys hate yours so badly, I will gladly take them off of your hands. The photon clip is MUCH bigger and unnecessarily bulky.