I dont know why, but I want to somehow validate my opinions on this matter...
8 years ago I lost a very close friend to pneumonia after a successful kidney transplant. The anti rejection drugs they give you after a transplant are essentially an artificially enforced AIDS - they suppress the immune system to prevent rejection. the biggest drawback here is even the simplest infection, a common cold or similar can grow and kill the patient. And it happens fast, 3 days in my friends case...
When it was determined he needed a transplant, I did what any true friend would do, I volunteered to be tissue matched. It turned out I wasnt a match. But if I had been I would have donated without a question.
When he died, it really screwed with my head for a few weeks, running all the 'if only' scenarios. But I eventually realised that even if it had been my kindey, there would have been no guarantees. I came to appreciate the things we had done, and the time we spent together as good friends before he died.
The risks are very clearly explained to both the reciever and potential donors of a transplant. They wont even let you test unless you understand what you are getting involved in - at least in the UK they do.
That all being said, I have another friend who also had renal failure. I did not hesitate to go to be tissue matched, again I wansn't a match. This friend recieved a donor kidney 4 years ago. Having seen the decline of his health into renal failure, he has now resumed an almost normal life after the transplant.
You dont get many true friends in life...value each and every moment with them...