The only time I use one is if I am wearing heavy clothing. They do a good job of holding the clothes down so they don't get in the way of the string.

In most cases with a compound that fits you properly and with proper grip you shouldn't need one. Unless you have a very short brace height. I shoot with a slightly bent arm vrs straight as well.

I believe recurve and long bows are bit different though. I don't shoot them so I'm not sure. However a lot of the target archers I see shoot them use arm and in some cases chest protectors.

Paul