Both kinds of bike can be comfortable and for a 10 mile ride most of the bio-mechanical or aerodynamic advantage is not relevant.

I (at least used to) own both kinds of bikes and I ended up selling the mountain bike and kept my touring bike. In my opinion, there are couple of things to be aware.

1.) Road bike components tend to be more expensive and more fragile than mountain components. So, make sure you like the major components on the bike (brifters, crankset, etc...) before you buy it.

2.) Fitting a road bike takes longer and possibly more money. For me, it took a new narrower drop bar, and a shorter stem and quite a bit of fiddling time to get comfy.

Finally, I might be going against the grain, but I think for commuting it is best to stick with a chrome-moly fork. It's heavier but I think it's much more durable than carbon fiber.