If one is really concerned, they would probably be better off putting that $2560 into an extended powertrain warranty. Then they'd be covered for the potential water pump failure, potential PTU failure, and other potential powertrain related issues that may occur. For the UOA to be truly effective, you would need to do it more frequently than every oil change at some point. Perhaps every oil change until about 60-75K miles and then more frequently from there through the 100-125K mile mark until the water pump fails or is replaced before it fails. No guarantees though as it could let go while you are waiting on results from your last test.