No. Not really. No one has said they value their body. Not a single person. In fact, the discussors have -all- said they would like to change out for a more durable brain. So why are you saying that?
What we -have- said, or at least what I have said, is that there is a philosophical difference between us. Namely, you see consciousness as a still-frame, only the present. While I see it as a long line, and that any break in that line (NO, sleeping doesn't count. Our brains are still active during sleep.) is a death of the self, no matter if there is another being who shares all the same neural structure at the time of death.
And yes I am aware of the whole planck second thing meaning there technically -is- no continuous time-line, and time is packeted, but I'm basing this off the way my brain currently works, which necessarily works around that. As long as any upgrade to a more durable substrate includes retaining the same type of continuity as is currently in my brain from moment to moment, and retains the same neural imprint immediately after as what was in the fleshy-bits immediately before, then I'm perfectly happy, and indeed delighted.
To reiterate: We all, or most of us anyway, want to upgrade, but because of philosophical differences the implications to each of us of the different styles of upgrade are different. Those different styles being gradual and awake replacement of structures, or individual neurons in the brain, until a complete reconstruction has been achieved VS whole-sale copy and destruction of the original, and anything in between.