I live in year-round high heat & humidity (in Singapore), so occasionally carrying fluid is a necessary evil here, at least for my long runs. But I hate to do so and have experimented with a number of hand-helds, belts and packs to find something comfortable. Everyone will have his or her own preferences, but I prefer a belt over a pack (though the small Nathan pack is ok) or hand-held bottle(s).
Among the belts, I've accumulated over the years a 6-bottle Fuel Belt, a Nathan Speed 2, a Nathan Speed 4 and an Ultimate Direction Thunderbolt. The most important thing is a fit/design that minimizes bouncing. The Fuel Belt is the worst on that score, so I don't use it. But it does carry the most bottles. My favorite is the Ultimate Direction, and I'd rate the Nathans a close and acceptable second. As for bottles, the Nathans and Ultimate Directions are a bit larger I think (10oz vs 8oz I believe for the Fuel Belt bottles), but they tend to leak from the spouts, which I hate. So I now use the Fuel Belt bottles (which can be bought separately in a 6-pack fairly cheaply) with the Ultimate Direction (3-bottles) or Nathan (2- or 4-bottles).
Hope this helps.