I've always stuck with a hi-capa 5.1 because they're accurate, reliable, left-hand friendly and easy to find parts for. Both of mine have been made by WE-tech. The first one I bought about 5 years ago was very plain but sturdy. It shot great great, but the slide was a little too heavy, so rapid fire would only work on extremely warm days. My new one, also made by WE but liscened cybergun, has a much lighter slide and shorter guide rod, making it much more gas efficient. Hi-Capa's also have an easy to adjust hop-up. The KJW Sig's are also very well made, and the NS2 models from KWA are pretty much the best around. Brands I would avoid are HFC and Bell.