I live in Singapore and deal with tropical heat/humidity all year long. I have used everything: belts (nathan, fuelbelt and ultimate direction) , packs (nathan) and hand-carried bottles. Everyone will have a different preference, but I don't like the hand-carried bottles and was only ok with the pack. The pack will make you all that much more hot and sweaty on your back, let alone bouncing around some and putting weight on your shoulders (which tightens me up). But I did think that the smallest Nathan pack (HPL 008) was pretty good if you prefer a pack. Of the belts (and packs too), it's all about finding one that bounces the least. I bought 3-4 of them over the years, and I like the Ultimate Direction Thunderbolt better than Nathan or Fuelbelt. My recommendation is to get the smallest belt or pack that you think you can deal with and then plan to stop after an hour and refill at a drinking fountain. Carrying 3 bottles or a smaller pack and refilling once is way easier for me than starting out with a ton of extra weight. Good luck.