As you aptly have picked up on, handheld releases are more prone to fit and shooting style issues than wrist strap types. To that end, you may very well end up going through quite a few releases before you find the one that works perfectly for you.

Given that, I would go to the "other site" and start off with something out of the classified section. It will be about $25-$50 off of the retail price, and most likely was bought and ultimately sold by someone in the same position as you (Bought it, tried it out, and sold it with less than 500 shots on it). The other nice thing is that if you do turn around and sell it, you will probably get very close to what you paid for it.