This puts me somewhat behind the technological curve, but results in reliable systems onboard. If there are two similar products from different companies, one of which has been proven and one not, I will go for the one that I know works in practice. The marine market is a tough one for equipment makers because of its relatively low-volume sales and high marketing overheads. A lot of people and companies come up with a bright idea and think they will make a killing. Regardless of how good the product is, they find it takes a great deal of money and effort to create a market.
Many companies fail before they get there, in which case there is no continuing product support.
This is of particular concern if you're buying a boat that has been built overseas or if you plan to go long-distance cruising. A 220-volt AC generator, for example, will not be much use for domestic cruising. If equipment fails out in the boonies, I want to know that I can either get it fixed locally or get repair parts shipped in quickly. The latter is a little more expensive up front, but is just about bulletproof, is virtually maintenance-free, and has almost no associated operating costs. Take, for example, a metal fuel tank more or less built into a boat.