I personally think the XCR resin is an excellent product for skinning pieces. I don't skin that much pieces because I prefer using moulds and resin infusion or prepreg, but when skinning pieces XCR is the best resin I've tried so far. Never had problems with it so far. Just need to be sure to mix it well and use it in the correct conditions like on the TDS. 
Most important thing is to use it in a stable environment, so avoid having big temperature changes.