I had the mesenchymal stem cell transplant (no ablation) through Dr. Slavin in Israel. The treatment was fairly expensive, but I definitely had some improvement. Almost all of my symptoms that I had before the treatment went away within 3 months after the treatment. Oddly enough, I fell into a relapse about 1 month following the treatment and experienced new symptoms I never had, though the old symptoms remained clear.
There is a lot of discussion about different stem cell treatments on MSWorld -- http://www.msworld.org/forum/forumdisplay.php?f=79
I've never heard of an ablation treatment without stem cells, and quite honestly I don't see what the point would be. First, there is growing evidence that the immune system plays a different role in MS than originally thought, so wiping it out may be somewhat useless. Second, without the healing effect of the stem cells you end up with no immune system and no way to heal all the damage. Third, ablation is VERY risky. I believe there may have been a death in one of the ablation studies, but I don't know which one... Maybe Friedman's study? Not sure. Anyway, I personally would not consider the ablation, and definitely not ablation without stem cells.
Regarding the cleveland clinic stem cell treatment, is this a study or are they actually offering this as a treatment? If you can get enrolled in the study I say definitely go for it. Generally all the stem cell studies I've read have been positive, and here's an article summing up the success of mesenchymal treatments and urging their use: http://www.ncbi.nlm.nih.gov/pubmed/20665128
One last thing. I would urge you to consider only stem cell treatments that are from autologous stem cells, meaning they are your own. There is a smaller risk of adverse effects.