This is just it though, isn't it? Sort of like Transporter technology in Star Trek, wherein everyone ignores the elephant in the room - all their friends died

This is just it though, isn't it? Sort of like Transporter technology in Star Trek, wherein everyone ignores the elephant in the room - all their friends died years ago, many times. Sure, they've a technology which creates perfect facsimiles after de-materialisation, but the Spock you knew and loved (or, at least, tolerated), and were just speaking to on-board a few moments ago, died, along with you, when you beamed down to the planet's surface. Much like normal neuronal biological growth, we'll need for the process to be as subtle and time-spanning as we can, presumably matching neuronal growth rates, so that we don't notice that we've killed ourselves in the process.