Most of the time it improves their quality of like significantly. It frees up their schedule and diet a lot. They have more hope for the future.
It's not without its risks and complications. A number of my patients suffered complications during or after their transplant. It should be viewed as a treatment option, not a cure. The burdens are shifted around (more medications, having a compromised immune system) and most of the time that comes out in the patient's favor.