I've been using AMK stuff for years backpacking and biking, and can attest to the quality of the clear zip pak they use.  I have a Pocket Medic Kit that has ridden in a backpack, pocket, suitcase, or bike seat bag for years without a tear or puncture.  The zip seal is really heavy-duty.  I just change out the perishables and away we go.  I believe I even sat on it once and didn't pop the seal.
I think this kit will be a great value.  
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Regards,
Gear Freak
USA