Actually, I have. It was a relatively small bird, I think 11 pounds. I cooked it on my rotisserie on medium (about 325 degree I believe). The key is to get the core temperature to 165 degrees, I believe. IT CAME OUT AWESOME. Self basting and absolutely luscious! I did have to tie the legs together so they didn't flop around too much. I removed the little popper thing, but you probably don't have to.
The size of your grill will probably dictate the size of the bird. I could not have gone much bigger, and I have a rather large grill. Great luck to you!