Your Hyperflow filters down to .2microns, the Frontier Pro down to .3, and then the MP1 tablets acts as backup or layered purification? The system seems, since we're in a UL forum, to be redundant and, the dreaded, "heavy". Here's a good article on the topic of water purification. I really appreciated his "Hyperbole" subject, as I believe there's less to be worried about in these water sources, e.g. High Sierras, then we're led to fear.
Sorry to derail the original post. Personally, I've replaced my bladders before the stress marks get too pronounced. And I've never had them prematurely leak. I think it's only realistic to appreciate a certain longevity of the product, and then be conservative about replacing them before too long. If it's a real concern, just buy a new one before the trip.