Sports drinks

In preparation for my planned but as yet unsigned up for 1/2 IM next month, I've been experimenting with various sports drinks. My stomach is much touchier than I would've given it credit for it seems.

Gatorade doens't seem to have enough go power for me. Accelerade felt a little heavy in my stomach alone, although I don't recall if I had any really serious upset from it. Cytomax is just nasty. So I tried a 50-50 mix of Acelerade and Gatorade which worked well on a couple of training rides, but I noticed as I drank more of it and my intensity level went up I was having some cramping and, uh, other issues. I used it yesterday in my race and my stomach sent me the big red flag warning ...by the run I was badly cramped and it sorta destroyed my run time I'm afraid. (My asthma didn't help matters any either. Probably neither did overdoing it on the bike. Ok leave it for the race report). Today I'm going to go back to straight Accelerade and see how I do. The problems actually seem to start when I use the drinks AND gels during the same session, even if I try to leave a few minutes between consuming the drinks and gels (washing gels down w/water of course). I can't see getting through a 1/2 IM without them both though.

I'm just wondering if anyone has anything they've tried that has worked well for them?