Thanks to folks like you, this thing may go down by $100 in a couple of trading sessions. But over the long term consider this:
If Mr. Market is willing to pay 68 for AMZN with all the competition it faces and net margin of 3.4, ISRG is a better buy with net margin at 27. As far rest of the medical devices industry, does ISRG really have any peer FDA approved robotic surgical devices makers to compare with? Is there really no difference between dentist chair manufacturing and ISRG's robots?