I currently have a profile design razor on my downtube and I would like to put another bottle on the bike for longer rides and have an area for extra tube, CO2 cartridge, etc, etc. I have looked at a lot of posts and it looks like a lot of people like putting bottles on their aero bars but I don’t think my 310XT and a bottle are going to fit up there so as I see it my choices are another razor on the seat tube and a small bag behind the seat or a behind the seat bottle holder in which one side gets used for extra tube, etc. Many may think this is another stupid aero question, which it may be, but I bought the bike for the slight aero advantage and would like to keep it as much as I can. I think the Profile Design Razors at the bottom of the frame create a P4 like area that may actually enhance the airflow over the bike, of course I have nothing to back this up. Which of these set-ups would you consider more aero or throw out another solution if you have one?
Thanks for you comments in advance.