I was going to go FG but ended up with concrete because we did want the custom look. Biggest pros for FG are, as said, less chemicals and (unsaid) no swimsuit or skin scrapes/sticking.

But I'll tell you -- I *love* our concrete pool and am glad we didn't go FG. I've swam in a lot of FG pools and they always seem "hollow" to me -- can't explain it any other way. I don't like they way they sound or feel. Concrete just seems more permanent and more pool like. In any case, our pool is a showpiece and that could not be said for any FG other than a custom design (which is probably out of the question for you or nearly anyone else).