For the past two years I've had an inflatable ring (14'x42") intex pool which was on dirt that I won't say was "perfectly" level although it's NOT terrible. We just had to fill it a bit lower, but it lasted for 2 seasons. The only reason we don't have it is because the sun baked the plastic into a crunchy texture.
2 months ago we had a 4"+ thick (with rebar) stamped concrete pad poured in the place we've had the pool. This way it can function as an extra patio in the winter months. I would certainly say that it is "more" level now but there's still a slight slope to it.
I'm looking at buying an ultra frame (14x48") but I'm curious how they can handle the slight level issues as compared to the inflatable ring type. I can certainly use pavers to level but I couldn't tell if the pavers were being used only to prevent sinking in dirt or if they can also offset level issues.
Any help is greatly appreciated!