I doubt that many external auto tuners these days would fail in the early years by being used intermittently for a month or so 24/7 every once in a while. There are several mechanical relays involved, the rest is electronic components. It is possible that the manufacturers have data (or educated guesses) on failure rate vs use. Most mechanical relays have such stats. Last month one of the first "HD TVs" I'd had for 12 years failed. That TV was on a lot over the years. There use to be a colloquial saying about these 'modern electronics devices:' If you turn your TV on and off several times a day it will last about six or seven years. If you leave it on 24/7 it will last about six or seven years.
In my case, I'm 83 years old - and hope to out live my remote auto tuner.
