We are considering a generator for our place in mid-Michigan. The problem I have with the pto option is that I only have 1 tractor. I might have other problems if the power goes out, like maybe a foot of snow.
Disconnect the PTO shaft and use the tractor for something else, then hook it back up. Unless someone's doing surgery in your house it should be OK for an hour or two without power. The other problem with small portable generators is that they like to be stolen.