It's been too hot here to make coffee, so Carole and I have been knocking down 5-hour drinks (actually the Costco knock-off), Red Bull and/or Rockstar. All sugar free. Some of the energy drinks work better for me; I keep forgetting which ones. The main problem is that I tend to crash after the time period. Well, I needed the nap, apparently, and five hours is usually enough of a boost to last. Not as good as a Depth Charge (coffee with a shot of espresso) which they serve at Convergence.

Anyway. What I would recommend is that you don't have too many (no more than one five-hour per day) and drink slowly. I looked at the ingredients, and it's all good stuff, but Romm's first and second rules for responsible drug use apply to energy drinks.