After looking at the specs on alot of .21 engines lately I'm wondering why the O.S. .21TM is so popular. Spec wise it has roughly the same RPMs as much of the motors in its price range or lower but you can buy engines like the Dynamite Mach 2 that put out .5 more HP than the .21tm for about half the price. Is the .21tm a small block and thats why it has less HP than other .21 buggy engines? Maybe because they come with either a revo or maxx headers and they are a direct drop in? Sorry I'm not overly familar with nitro engines as I've only had about 3 different models one of them being the .21TM that I've never used I'm just curious why this is such a popular engine. I mean i know that OS quality is higher than dynamite but other than that can anyone shed some more light on this for me?