I had a negative experience with a shower cartridge from Moen. Contrary to its reputation, Moen is the cheaper quality sister company to Riobel, which has a somewhat better reputation. A reputable plumbing supplier told me that at the same price point as Moen, Delta offers better value. At a higher price point, Grohe has higher quality. I don't accept that things should be designed to last only ten years, particularly when they don't get heavy use. In this case, I used the shower at the gym regularly, and rarely used the one at one after it was installed. The cartridge calcified, as heir designers should expect when water is moderately hard as mine is. It was difficult to speak with Moen by phone, and they gave very confusing (and partly incorrect) information on Allen key sizes and decalcification of cartridges. After a second call, they sent out a replacement cartridge, the correct Allen key, and very complicated instructions for a complicated product. As I'm not very handy, I was never able to disassemble it fully - and I needed to call a plumber to resolve the situation, at my own expense. The trend (as with many other manufactured products) is to make things both more complicated and more cheaply, usually in China. Moen is no exception. My Dad (who was a plumber) always tried to install products which would be of quality reliable and relatively simple) would not have been pleased with this situation either. Shower systems should be as simple as possible, and not easily become clogged with minerals. If Moen / Riobel don't grasp that concept, aren't they forgetting how these cartridges are actually used? Surely they must have the resources to devise parts which repel minerals and don't clog? Shouldn't they have chemistry experts, particularly related to water and the properties of materials such as metals, ceramics and plastics?