at first I thought Hammer was more hype than anything but now I am convinced it works.
I absolutely LOVE the Recoverite. I mix it w/OJ after a hard effort and it helps me recover much better with less soreness. I drink it before I go out if I know I will be riding hard.
I tried Perpetuem just once on back-to-back centuries last season and it just didn't sit well....maybe I need to give it another try, though.
I know that the Hammer literature does not recommend mixing their products w/other products that contain simple sugars (like gatorade) I don't know if that's just so they can sell more of their products or if it's actual science.