I really like the Tru Ball cyclone release. You pull the trigger to open the jaws and let up to close them. You can also adjust the trigger sensitivity adjust the length, and much more. I really think this is the release to buy. The first link is the link to the cyclone and the 2nd is the link to tru ball.

http://www.truball.com/Pages/3cyclone.html

www.truball.com