I had a GTO Pro for about 9 years, it was a higher end unit than the Mighty Mule, more expensive but worth the money. It died and checking the info on the internet the cost of a new control board on a 9 years old operator wasn"t good sense. Checking the then Mighty Mule and GTO Pro series for costs and so forth I found the reviews were medium to poor, support was also rated less than satisfactory. I went with a Sentry Unit. It is guarenteed, if memory serves me right, for 10 years. I mounted both units myself. I believe the Sentry is a better built unit. It does not open as quickly as the GTO Pro did but it is fast enough that I don"t break into a sweat. It has a battery but can also be run on 115v. The battery is supposed to be good for 50 openings absent AC current. I"m satisfied with it and would buy again if their ratings are still good.
Bob in Central Arizona