I'll give you Accelerade drinkers credit, that stuff is vile, like fatty gatorade. When it gets warm, hold your nose while you drink. It's also rather expensive.
My opinion only, others may like it.
My goal is re-hydration not caloric intake nor electrolyte replacement. I drink water.
I would consider caloric and/or electrolyte replacement if I were swimming for an extended period of time. My workouts are 1.5 hours and I find water quite sufficient.
water, just simple water. The bottle also serves as a counter for me... laps 1 to 10 the bottle sits on right side of workout, laps 11 to 20 the bottle sits on left side of the workout... or something similar that fits the swims of the workout I am doing that day. Stopping briefly enough to move the bottle helps remind me to keep myself hydrated and take a sip... then off again.
Water mainly for me as well!!!!! Gatorade/Powerade...all of those are high in sugar! I want re-hydration...water is best! Sometimes a gallon or more a day, a glass here and there all day and I am fine. Sugar = simple carbs...good for short bursts of energy. Noodles and such are complex carbs, better for the long run.:D
Over 1.5 hours- 1/3 red (ONLY red) gatorade + 2/3 water. Over 3 hours- 1/2 water + 1/4 red gatorade + 1/4 coca cola. Its pretty color ensures that no one will mistakenly take my bottle while I'm gone!