I had a pair of concert Fleas, one with the plastic and one with a rosewood fretboard. To be honest, I like the feel of the plastic one better, and ended up giving my rosewood-fretted Flea to a family member. But they both felt good - it's just that the plastic one felt smoother along the edges.
I've been playing my plastic-fretted Flea and Fluke extensively since 2009, and am starting to see some slight wear on the plastic frets, but it hasn't become a problem. The biggest downside of the plastic fretboard is that the frets themselves can be hard to see. If you look at the neck a lot when you play, you'll have an easier time with conventional frets. But if you're past needing to look at it very often, this problem goes away, too. Both the plastic and rosewood fretboards were perfectly in tune all the way up the neck.
The frets on the "Fake Flea" from Schoenhut seem to be a little thinner than those on the Flea, for what it's worth, and was not glued to the neck nearly as precisely as a real Flea. But it still has good intonation, just crappy tone.