The problem with mind uploading is you lose your sense of identity, it's no longer you, your consciousness has been moved from one body to the next, turned from chemical reactions to light, so you are essentially making a clone of yourself that is exactly you. It's the concept that the individual dies, replaced by a new, exact (and even superior) individual. I don't exactly know what indefinite life expansion is however. So, I'm gonna say mind uploading, with that issue in mind.
If you had a choice between two Valve weapons, would you pick the gravity gun or the portal gun?