There are TONS of electrolyte replacement drinks out there that work great... but there is only one with a patented 4:1 carbohydrate to protein ratio: Accelerade.
I used to use the predecessor to this awesome product called Endurox R4 as a recovery drink when I was in the game. Then they formulated a during-exercise, protein enhanced sports drink in powdered canisters, and now they have READY TO DRINK bottles popping up EVERYWHERE!
Stop by the Vanderkitten booth at Sea Otter and try out the new flavors and decide for yourself. I find the protein cuts the acidity, a problem I have when going all-out and needing a sports beverage. It also has some major advantages in recovery on and off the bike.
The appealing packaging is also preferred by Raycer, hands down.