There's a great article at The Wall Street Journal from a reporter documenting her ongoing frustrations with the systemic problems with the new Macbook keyboards. This aligns with my own experiences with the computers I repair, with some users experiencing the issue again even after "repair". The reason for this is that the replacement parts (which amount to basically the entire laptop chassis, since Apple doesn't make the keyboard a replaceable part) don't have the flaw fixed. So you're just swapping the failed part with an identical one that will probably just fail again in the same way. This remains the case even with the latest model Macbook, despite Apple having known about this issue for over a year.
I do always advise my clients to consider repairability and track record as a factor when they make their computer choices. Initial purchase price is just one of many parts of what amounts to the total cost of ownership.