Ive had the Autoformer for about 10 years now and really didn't use it much until I joined the "Zone Pass" with Thousand Trails! This is NOT a knock on TT but many of their Parks have older wiring and in many cases Aluminum wire. I now use the Autoformer all the time especially where there is a high demand for air conditioning on old 30 amp pedestals. Has worked Great and does what its suppose to do...I do use it in conjunction with a Surge Guard.