Thanks to a recent acquisition, I'm up to 18 but must admit that one A500 is a bit flaky and one A1200 is complete and fully functional minus the case.
(for the purists, I didn't count the two computers that I regularly run WinUAE on.)
I do use them all quite often, but always gravitate back to using my original 1987 purchased A1000 more than any of the others. No special reason other than it feels like quality time with an old friend.
Regards,
AmigaEd