Stylite Foam - Anybody Used This?

I'm interested in this foam board called Stylite, possibly for use in
GRP. It was apparently designed for displays/presentations/trade show
kinda stuff but: it claims to be waterproof, fire retardant, rigid and
dense enough to work with a router, and a 3/4" 4 x 8 sheet:

--weighs a whopping 4.2 pounds

--costs a whopping fourteen dollars

--this ain't Airex.

I originally came across the product when searching for something to
use for panelling/flooring, not structure. Glass it, then vacuum bag
veneer it, thinks I. The 1/2" sheets are 2.8 lbs raw. Seems like just
the thing for building the interior of a multihull.

Then I thought about building a canoe or something with it, just to
see.

For all I know the stuff melts into a gooey round ball when it touches
rosin.

Anybody tried it?

--
Hoop
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