Get what ur gut calls for. I run dynamite euro xpe .21(basically a alpha with a diffrent name and color head). I love this engine, but i know Robert will not support junk and sell/run junk so i assume GO is GOOD to. Now u asked good for a buggy, well alpha marks the orange head as 1/8 buggy but there is no "buggy" engine. You can put a .28 or even .30 in buggy if you want lol. Me i would say Alpha but i know GO isn't a bad mill either but alpha is worlds warm-up 2010 champs lol. Honestly buy what you want and whats poppular at the lhs tracks. Nothing worse having a tune issue and no one knowing the engine to help you. Also throughing this out here Werks b5 or b6 are also really nice and easy to tune engines. I would say werks and my alpha based dynamite are my favorite mills so far.