Forget all that. That Mega ZX12 race is the best thing out there. It is a PAIN to tune and the conrod needs to be replaced after a few hours, but that will be resolved shortly. (and even still they're cheap) I'm closing in on Gallon #2 and the sleeve is still great, that engine never had a ton of pinch out of the box, but it still has plenty of compression even when hot. And it's still idling well and really low. I'd gladly choose it over the V12 (which I've run) and the TZ any day. I'm not a Serpent guy and in fact was pretty disappointed with the Mega at first. But now I love it once I really learned to tune it. Now throw in the money factor, which I know you said not to, but for $265 WITH the ideal pipe designed for it (which retails for over $100 ALONE), you can't beat it.