I don't know what it's like there but around here you probably couldn't keep up on a group road ride with a mtn bike. We have a breakfast ride every month and we usually have one or two people with mtn. bikes on those rides. And that's fine 'cause it's an easy pace. I rode my mtn. bike on the road a few times but then decided to get a road bike. You will enjoy your rides on the road a whole lot more with a road bike... but if that isn't in the cards for you then just ride whatever bike you have - to heck with what anyone else has to say. Just have fun!