I have used this belt on many occasions. Everything from long training runs to lengthy races, the latest being the Ironman Lake Placid. There a few key features that makes this belt a good fit for every type of athlete.
Size/Fit:
With having a Velcro strap to attach the belt, it gives you the flexibility to find the right fit. I typically wear a medium/large pant, so I went with the medium belt and it fits reasonably well over my running gear. I would suggest suiting up in your favorite running gear and taking a measurement to get an accurate fit.
Comfort Level:
I have heard different reactions from different people regarding the fit. I have noticed the belt is only slightly noticeable when you first put it on and start running. Admittedly, I forgot about it after a few steps, which is just what you want. Also, the velcro strap and the limited stretch waistband provide a secure fit without being too tight.
Fit during a run:
No bouncing. I did have one problem with the belt, however. It started to slide upward during the run, forcing me to adjust it frequently. In fairness, however, this was only a small inconvenience when compared to the great benefits of this belt.
Bottle Cage:
The bottle cage has a nice molded shape to it that make a good fit for the Nathan designed bottles. They are made from a flexible plastic. The cage is sewn directly to the belt by way of elastic straps. The bottom strap keeps the bottle from falling out the bottom. The sides are attached by 2 short elastic straps on each side of the cage that have 4 strips of a rubber-like thread that give extra grip to the bottle to keep it in place.
Front Pocket:
The pocket is sufficient in size. I comfortably carry gel packs, sport beans, sunblock stick, or anything else that would help during a race. You could also fit your cell phone, money, keys and other things that you would need during those long runs.
Overall, this is a great product. The 4 bottles (8 ounces each) belt is sufficient for someone completing long runs around 3-4 hours, depending on your hydration needs. If you are completing shorter runs you can get away with the 2 bottle belt. I would highly recommend this product for anyone looking for a good running partner to help carry all your hydration/nutrition needs.