Did you swap your old brain for a new brain? Do you have a different set of eyes now than you used to? No? Then your analogy doesn't really work. I, on the other hand, no longer have the lenses in my eyes that I was born with. After my surgeries last year I have an artificial lens in each eye, and a card for each of them to show in case anyone ever needs to know. I joke sometimes that it gives me bionic vision like Steve Austin (it doesn't, but it's bemusing to see the occasional person have a "wait, what, really?" reaction), but what it really means is that I'm not blind, as I would have been if the surgeries hadn't been done. It hasn't had an effect on what my favorite color is or that I still perceive the key of B-flat major as purple.