I used to ride with a hydration pack all the time. After getting into racing and ditching the pack for the shorter races I felt pretty free and lighter without it. Gradually, I was able to adapt to the longer races and found ways of carrying everything without the need for a pack. I hardly ever ride with one anymore. It has it's 'pros' and 'cons' of course.
- don't have something heavy, bulky on your back
- less weight
- sweat wicks away better
- more exposure of your jersey (especially important if you are a sponsored rider)
- easy access to rear pockets on jersey
- you don't have to stop and take off the pack to find items
- can't carry as much water, tools, gear
- your jersey can resemble sagging boobs - but on your back - saggy back boobs
- any tools, tubes, air that's on your bike can get covered in mud & dirt, for example......
There is . . . check it out. Would love to get my hands on one for those muddy rides, i.e. Crank The Shield (should be given out at the beginning of the race - might be a cool piece of schwag kit instead of this lame hat).