FIT is the most important factor in a PC for me. Its even higher than durability. Unfortunately, you have to buy one to test it and the first won't likely be the one you end up with.

This is how people like me end up with countless piles of stuff.

As greaser said: google, read, and take the plunge. You aren't likely to get your answer here. I've posted my knowledge already, and don't think there are too many here that wear them.

My only parting thought would be: DO NOT CHEAP OUT. You won't like the results.