Personally, I prefer the XLAB Saddlewing over Profile's Aquarack simply because you can attach some CO2's, an inflator, and some tires/tubes if you choose to do so. However these are a little more expensive. If you do lots of long training rides, this is the ticket in my opinion.

With that said, in a race I would stick with on the frame cages and an Aerodrink up front. Think of long races as catered training rides. You really shouldn't need any more than two bottles at any given time and some new wind tunnel data says that you are more aero with bottles on the frame anyway. Conventional knowledge used to say that the bottles were "hidden from the wind" behind your back, but really there's a lot of air streaming down your back that gets caught by the bottles/rack. Kind of like a spoiler on a car. I guess this is good if you need more downforce on the rear wheel. : )

Hope this helps!

If you decide that you want an Aqua Rack, I can make you a deal on one that was barely used and is just sitting in my garage.