Arm vs. Leg?

I voted for leg and I'll tell you why. The anatomical definition for "leg" is below the knee. That being said, success rates for young healthy people with the use of prosthetics is high. Great advances in prosthetics have been seen in above knee (trans-femoral) amputations as well, i.e. the "c leg" With proper training from a physical therapist (I had to throw that in) one can function at a level close to their previous baseline, running, skiing etc.

Perhaps you do not find your non-dominant arm useful, but there are many things throughout the day that you do with both extremities that you don't think about, i.e. typing, steading a sheet of paper while writing, reaching for objects above head, dressing (buttoning etc.). In addition, prosthesis for upper extremities are not nearly as advanced as for lower extremities and are much more difficult to master. Not only that, but they can never help you regain a lost function such as an artificial leg can. Occupational therapists can help you adjust your life to your deficit, but you cannot adjust your prosthesis to your life.

Plus, I'm a physical therapist so I would have an advantage in self management, i.e. stump (residual limb) care, and prosthetic training.

Initially I inclined to agree with your comment, but then I thought... "Gamers!".