That will cover any number of OS X devices. I think there will be money back if you don't like it !
I had a snag once , the support is amazing , a smart guy from Agile called me back and talked me through an upgrade.
Its a bit like "having two chefs in the kitchen", (could get messy) , you must let Password do everything and turn off the apple keychain stuff.
I hope you like it , I do !