i have a 30x40 shop i built about 7 years ago and did in floor heat, if i built another shop i would do it again, i love it. its silent i hate listing to a unit heater run. its heated from October to April at 60 degrees, i use to have an hour meter on it so i could monitor how much it ran, i stopped paying attention when the batteries died but it would run on average about 1.5-2 hrs a day, depending on the outside temp. i would guess its about $40-50 a month to heat it. i do wish i had a way to measure just the gas consumption for the shop compared to the rest of the house but i haven't found a good way to do that. the big thing for me as mentioned above is everything is warm. the more stuff in the shop the more efficient it is, everything is like a thermal battery. the heat is very even the floor and ceiling are the same temp. i don't understand the comments about recovery time, if i open a door to pull a vehicle in or out it will kick on for a few minutes and shut back off the temp is back almost immediately, the air just needs to heat back up since i have a regular thermostat not a in slab probe it will cycle for a few minutes. one thing to think about is if you're not willing to invest in good insulation it might not be worth it. i have R30 in two walls, R36 in two walls and R30 in the ceiling with insulated doors and 2" under the slab. as far as maintenance i have done nothing to it since i installed it and got all the air bled out, it sits for 6 months after April turned off in the summer and i flip the switch and it fires right back up in October like it never shut off.