I keep a back up. I lost mine in the woods once and it ended my hunt. I didn't even thinkabout trying to shoot a deer without it.
You really can't shoot a bow tuned for a release with fingers. The way the arrow bends it needs side-pressure to help it fly straight. Most release shooters use a shoot-thru or prong-type rest. Even with a Wisker Biscuit the arrow wouldn't hit the same as with a release.
Check it out; this is a fingers-release:
http://www.youtube.com/watch?v=SuHW8InB5tk&NR=1
With amechanical-release the arrow arches upward because the string stays in-line with the arrow.