Thank you, all for the info.
I'll admit price is a factor for me but so is weight and to a lesser degree fear of damage. I don't wheel much in the way of rocks or at least haven't yet, but my tailgate has tasted tree and it has "custom bend" in it now. Since we tow our JKU behind an RV on trips sometimes, I think polymer would save me a lot of weight.
As it is, our Jeep gets thoroughly soaked so often I don't even leave the drain plugs in it so I don't know if rain leaking around a soft top is that big of concern to me. Maybe I just don't realize how much leaking you're talking about?