I've been using a 10" pair for a year now with fibreglass boat repairs and the like. I've really tried to abuse them, trimming door skin templates, trimming cured fibreglass sheet, thick multi-layer glass fabrics, rubber, plastics, and these haven't missed a beat. They've been soaked in resin, washed in acetone, and put back to work several times. The old Wiss used to be industry standard and in every fibreglass shop. These shears are as good or better and look great!