I see other reviewers are having problems with their Soaker 70s, but not me. I use mine for biking to/around/from work (5-10 casual miles per day) and sometimes for longer days on the trail (~20-30 miles.) I received it as a gift when I went out to BurningMan a few years ago, and it was a lifesaver in the desert heat.
It's small enough to be lightweight and comfortable, yet still has enough space to secure valuables. I haven't used the hidden mesh pocket yet, but it's nice to have just in case. The water tube can be routed over the left or right shoulder, and I use the loops on the other side to route MP3 headphones. Then secure the MP3 player onto the clip on the back, set it to shuffle, and hit the road ... everything I need is on or in the pack.
It has always held up great for me, and cleans up easily. (If it can survive BurningMan and still looks like new, that's impressive!)
It leaked on me once, after cleaning it, because I didn't screw the water tube in tight enough. A few turns of the tube, and now all is well.
You need to mind yourself when taking the bladder out, it secures in there pretty tight, but it IS removable. The extra five minutes of my time spent taking it out is not that big of a deal, especially considering you only have to clean the bladder every few weeks or so (depending on use.)
Overall, I find my Soaker 70 useful and a great value!