So I have a mountain bike .. a trek X-caliber 9 and a fat bike Framed Alaskan aluminum. I've been tossing around the idea of getting a road bike. 80% of my riding is on dirt/paved roads. I am perfectly happy cruising around on mt. bike on dirt roads and hitting the trails with my fatty.But I go to bed at night thinking how cool it would be with a road bike hitting the pavement. Question is.. how much better/faster/comfortable is it with a road bike on hard pack/pavement vs a mt. bike?