As I have been in fact finding mode for backpacks for a few months now, I have been following the various threads here with much interest. While doing so, one nagging question comes up, how do you buy a pack without having actually tried it out? Most of the recommended gear is available online, but with the exception of REI and EMS, there are no brick and mortar stores near me to do a hands on. At this point, I'm not even sure whether to get a full pack or a three day without seeing their specifications.