As with most things with our boats, everything is a tradeoff. I personally believe that a fitted canvas tarp is best ($$$), shrinkwrap next to best ($$), and inexpensive blue poly tarps are adequate, if used "properly" ($). I have been using the blue poly tarps for years and like them. I find the key to their use is to add support clips in between the gromments and make sure they are tied tightly to the toe rail. On my H28.5, I use 3 separate tarps: one over the bow, one over the boom, and one scrunched in under the boom and over the pedestal and tied to the stern pulpit. This gives me coverage from snow, ice, rain, and bird poop over about 95 per cent of the boat and works well for me. I typically get 3 years use out of a set of these tarps.