You need to ask yourself this question. If mzor captures 100% of the scoliosis surgery market, how many procedures will they get? I have a number. I would be interested in what you find.
I bought Mazor in mid-summer and still hold it. It has had a meteoric rise over the last 4 months so I don't think I'd add to my position until it either settles down or grows into its current valuation. It should work out well, but I certainly don't expect it ever to attain the value of ISRG.