Who has a back up generator (permanent install)

We are getting one for the Mother in law who is 81 and still lives outside of town on the farm. I see a lot more permanent ones being installed on newer properties and acreages. We are looking at Generac because of 2 local dealer/installers. I also see Kohler and Onan but those 2 brands don't have a very solid dealer network in her area and I have found service and warranty coverage is quite important. What are you running and how has it been?