When you shop around, see who has the the best structural support. If you can find out the actual metal thickness of the side wall, the top rail, the vertical upright columns, how many vertical columns are there between the different pools etc. Simply put, bigger, thicker, wider, sturdier, and more is better. Compare the bottom rail that sits in the ground. Is it wider, is it coated, is it galvanized? Do the vertical uprights require additional supports?

I had an 18' pool that bulged all the way around the side wall. The Pool store came out and install additional supports in the uprights because the initial ones were too thin.

Liners are another issue. See what liner thickness comes standard with the pool kit, and ask if there is a thicker upgrade. 20 mil or thicker is best. Some liners have a 20 mil bottom, but only have a 15 mil sidewall. Is it a traditional overlap liner or the new rail type?

I will be the first to tell you that some of this information may not be readily available, I would stay away from "DEALS" from unknown manufacturers. I like my Doughboy, but doing your homework may save you a little anguish in the long run.