Last winter in Maine we got so much snow that many of the above ground pools blew out the sides with the increased pressure on them. In ground pools didn't have a problem. Second, if you can get an in ground pool with 1 depth (like an above ground pool), you can then use the CHEAP auto vacuums. These units are only sold for above ground pools because they can't climb the slope between shallow and deep ends. The above ground units cost $300. The in ground units require a seperate pump and cost $1200 or more.