: I read a comment on another site that the RR epoxy didn't provide
: as hard (durable) a surface as say West's epoxy. Dan, what's
: your experience in that regard?

Limited to date. It seems very comparable to MAS. It would depend on what modulus resin they used. RR is one of the few suppliers of epoxy resin that offer different modulus resins. Each one is suited to different applications.

Below are links to the respective tech sheets (MAS had no data on-line):
http://www.resinresearch.net/id8.html
http://www.westsystem.com/ss/typical-physical-properties/

I'll compare a few values. RR first with West in parenthesis.

Resin Research 2000 resin (medium modulus for hand layups) w/2100 hardener (compare to West System 105/207)
Barcol hardness = 83 (84.4) (West 105/205 or 206 = 83)
Tensile (psi) = 9,800 (6,748)
Flex Strength (psi) = 14,800 (11,324)
Flex Modulus (psi) = 480,000 (412,000)
HDT (heat deflection temp) = 122F (117F)
Compression (yield, psi) = 15,400 (11,043)
% Elongation = 3.8 (3.8)

The surface hardness IS slightly lower but is the same as West 105 with 205 or 206 hardeners. RR seems to have much higher tensile, compressive and flexural strengths with a higher heat deformation temperature. I can see why Pat switched...