I was considering this type of therapy recently and also asked for input here at TIMS.
I have put it off for now. Based on the research I have done, I came to the conclusion that stem cell therapy is perhaps too new to try at this point, except as a last resort.
But on the other hand, there does not seem to be any down side (except for the high cost). Keep in mind that some, but not all, companies offering this therapy doing it along with chemo therapy.