Fiberglass cloth and resin for shower pan

Question

What are the drawbacks in using fiberglass cloth and resin for shower base with Red guard as opposed to rubber membrane?

Answer 1

Other way around.

With a pan liner you need to float a mortar bed first. Never done it. Not even sure there's a good question here about it. Best I ever saw was a comment about it... somewhere.

With backerboard all you need to know is how to use a screw gun and how to paint. But if it's eight feet square it might be difficult to pitch it right, which is where mortar beds come into play, or they start butchering your joists.

I switched to terrazzo long ago. It's expensive, but so are leaks.