As a family we have toured for the last 4 summers, we use a number of brands of panniers in common all nylon will leak sooner or later if it rains, just pack in plastic no big deal. The MEC system is solid enough for any on road or off road touring we have done. The arkel system is nice but heavy even when empty, remember you have to haul all that weight up and down the hills, the German sacs are plain and will float if the water is deep enough, but two problems, once your gear is wet its not going to dry in the bag ever, damp stuff does do moldy, get ugly. The simple welded sac design of the ortleibs is tough and long lasting but just too plain for my liking. IMHO the MEC gear is a good overall compermise. One more thing to remember is that if for any reason you do not like the stuff or it fails or you think it failed you are welcomed to return the gear to the MEC.