I have used the System III Silvertip and like it the most among West System, USComposites, and System III general purpose. I have used MAS in the past and found that the pumps supplied, dispensed too small an amount. However, with the teardrop trailer that I am now building, I find that with the temperature above 85 degrees F, I can alternate between one pump of each and never lose track of the proper ratio of resin to hardener (the temperature is important because below 85 degrees F, the spring pressure doesn't return the pump to full stroke position.) Another frustration I had in the past with MAS is that the resin always gives a drip about ten seconds after the last pump stroke. Those MAS pumps still drip, but I have decided to "Just get over it".

That said, the MAS provides a low viscosity layer with few if any bubbles, minimal orange peal appearance, great saturation of multiple layers of E-glass, perfect working time for me that sets up in 3 hours for recoating and 8 hours for sanding/scraping/cloth edge trimming (as does System III Silvertip). After 9 boats and 8 years of working in my shop, I have acquired enough skill at temperature regulation of the work space to fine tune to the temperature requirements of the material. If I were to change shops, heating methods, or materials, things would probably not go as well.