Tkn27 does a video on probably is already the most reviewed and customised airsoft pistol in the market, the Tokyo Marui Hi-Capa 5.1 Gas Blowback Pistol... "Commonly known as the most reliable gbb pistol on the market, the TM Hi-Capa 5.1 is truly a masterpiece. It has such a solid design that the majority of airsoft IPSC competitors use this gun as their base gun. As such, this is also the gun with the most aftermarket parts, letting you fully customize every single part! Personal preferences aside, there really isn't any major downside to this pistol, it's easily the best gbb pistol out there!"