In the year and a half since we put in the whole house genny system it has run a total of 7 hours 90% of which was from the weekly automated test run. I consider it a insurance policy which will keep me up and running for 3 weeks if it ever becomes necessary. It is especially good to know when you depend on a well for water.
Lol. I bought one in 99 as well. Its been used for maybe 10 hours of power outages spread out over all these years. It gets more run time being exercised vs actual usage.