No catch , I paid around $6 yd . Equal fiberglass is over $9 yd.
It does saturate a little slower than E-glass and you have to paint it , no varnish .
Works great with cheap epoxy $35 gal .
Only negative is, it uses about 10 to 15% more epoxy , which per square yd. works out to aprox. 1.5 oz extra.