I picked Cosmic Ray's for the selections. I've been to both and Cosmic Rays has everything Pecos Bill's has, plus a few selections. We love the turkey-bacon wrap.
Although it is perceived you can't get burgers on the chicken side, that is actually incorrect. There is a line open on the chicken bay side that offers burgers and hot dogs along with all the chicken selections, so it's not that big of a deal. The only open this line up during peak volume time.
Cosmic Ray's does have the little music show, but we haven't paid much attention to it. A couple other reason's we like Cosmic Ray's...there is plenty of seating. We've never had a problem finding a spot...and usually in the air conditioning to boot! The other reason we like it is if you do get "stuck" outside, the balcony area gets a great breeze and you can enjoy the breeze while people watching and cooling off in the shade.