Let me begin by saying that I have never been a fan of hydration packs. All of the brands I have previously used from Camelback, Nathen, Fox, Osprey etc.. always felt heavy and unbalanced and why I avoided using them but recently I was forced to ditch my seat bag to carry my spares and tools for my mountain bike because my new bike came with a dropper seatpost.Having read some good initial reviews of the Thule Vital I decided to give it a try and to my surprise this hydration pack was really awesome. The split bladder keeps the water from sloshing around so the pack feels stable on your back and its low center of gravity makes it really comfortable even on longer rides. It was so comfortable in fact that I had to reach up a couple of times and check that it was still on my body because it felt like it wasn’t there at all! Their “ReTrakt” magnetic hose system is really cool and makes it easy to find when on the trail and the side pocket placement is at the perfect location to easily reach your arm back for your nutrition needs. Like all of Thule’s products the quality is great, so if you are a trail rider just having fun or a racer looking for lightweight feel and comfort this I highly recommend this product.