The micro is the one engine with very different performance numbers based on the published power curves. For instance the Prevo peaked at 6.8hp at 6500 RPM and then continously falls off to 3.2hp at 10,500 RPM. the Evo curve says it peaks at 8.1 hp at 7000 rpm and holds the 8hp 8200rpm then drops to 7hp and holds at 6.5 to 7 hp up to 11,000 rpm. Then it drops quickly to 2.6hp at 12,000 rpm. so the hp at 10,500 is double the Prevo. There is about 30% more area under the Evo power curve compared to the Prevo. The Evo will be quite a lot quicker than the Prevo (not upgraded). Hoopefully the upgraded prevo will be on par with the full Evo. The current murmurs seem to be positive in that respect but we will soon find out.
This is all from PUBLISHED curves. Not real dyno data I have access to. SO it all depends on how much the BRP marketing department pencil whipped the curves.