Imperfect copies aren't the only non-technological problem with brain uploading as a kind of immortality. It only makes sense in principal if you buy a continuity of consciousness theory of personal identity. So, say you both can make a copy of your consciousness, and your favorite continuity of consciousness theory hold. Say you go ahead and make a copy of yourself.
The moment you do it, there are two yous. One of you is still made of meat, and is still going to die. One of you is not, and is not identical to the meat-you from the moment you forked (no more continuity of consciousness). So, even with the most generous assumptions, the best you can do is another person a bit like you.
We already have the technology to make persons a bit like us. Most of us figure out how it works as teenagers.