My barber competed in bodybuilding for a while and he said if you want to gain weight to eat a few more grams of protein as your weight in pounds and if you want to lose weight to eat slightly fewer grams of protein than your weight. I tried to do it for a little while but I haven't found a protein powder that I tolerate yet.
As far as the recovery drinks they seem to all work pretty great to reduce fatigue and weakness from frequent workouts. frequent workouts cause things like glutamine to be depleted faster than you can normally replace them.