Great for trail racing!
I got this pack for a recent Mountain 100 mile trail running race. I don't really care to carry water bottles when I run and this pack was the perfect replacement. The front pockets are a bonus for carrying trail food. Fully loaded I could hardly tell I was wearing it. Also, there is no waist belt to aggravate your stomach. Another thing I like was the transition speed for water refills. Didn't have to pull out the bladder to refill. This is definitely a racing pack.