I have no problem with this idea as it could save a family from losing their home by paying off the mortgage.  Pro-abortionists have been saying, "It's my body," so why not make this accepted philosophy equally helpful to those of us willing to face more positive medical risks.  Soliciting donors legally may serve to stop some of the criminal "organlegging" which has been going on in China for years.  For some unique thinking on this subject, read a few of sci-fi author Larry Niven's novels on the subject such as Patchwork Girl and Gift From Earth which contain some pretty alarming conjecture and potential horrorshow of the future.