I use one NUUN tablet per big bottle, a little diluted yes, but I like it like that.
I've tried one flavor of Skratch and didn't find it terrible, but the packaging is tough to open and it is another long narrow bag to keep track of. The tablets in a snack size zip-lock are easy.
I carry one bag of Chomps on long rides. I also put them into a snack sized zip-lock bag. Way easier to open and close even while riding.
Then for that extra kick when I really need it I carry GU, the one with double caffeine in peach. Doesn't bother me, but I have always drank an whole big bottle of water with it. Good for about a half hour or so in the hundred degree heat for me.
When it is hot, I carry and re-fill one large bottle of water and one same size of NUUN. No cramps and I can keep going.
I'll do a light night tonight and leg massage, then hydrate well for a big ride tomorrow. I hope to be able to get a medium ride in Sunday as well. It is going to be a busy weekend.