Here's a test I did on the Axe-FX virtual capo, testing with a variety of settings, and comparing it do the Digitech Drop. Someone correct me if I'm wrong, but I believe the FM9, unlike the FM3, has the same virtual capo as the Axe-FX III. You can hear the settings make a big difference, so choose those carefully.
Original, Digitech Drop -7, VC -7 Fast 5, VC Fast 10, VC Off 5, VC Off 10, VC Smooth 5, VC Smooth 10, Original.
There's an audible difference with both the pitch stability and the transient preservation, but thing that stands out to me is that you can get a good pitch shift with the Virtual Capo at amazingly low latency. At Fast/5 it's about 5 msecs less latency than the Drop.