In the 'less temperate' climes, there is often a discount for having the pool installed in the fall. They do this to keep their building season longer.
The problem is that the new pool owner gets the pool installed and then immediately covered and can't see any issues until the next spring. There is also the 'issue' of having a winter on your new pool before you ever get to enjoy it (though a properly winterized pool doesn't suffer too much, and you saved a bunch $$ to get it done in the fall)
In short, I'd say "Go for it!", but make sure that your contract says that they will fix anything you find wrong after a month+ of using it1