i like to include some road biking in some of my rides and some are entirely road rides. but i don't ride a road bike, i just pump up my knobbies to 65 psi. i ride the road to connect trails in order to make a loop or go on 50 to 62 miles fun rides. or i'll ride around the city to do some ride obstacles or do something technical/chalenging.
i sterted out on a road bike but after dinging my rims, i got a MTB and never looked back, that was 1990. now i do everything on knobbies.
i did the Rosarito to Ensenada 50 mile fun ride just barely under 3 hours (2:59:34) and plan to do it again on Aprill 22nd if anyone wants to join me. (i'll post the ride later on)
all my buddies and myself do Fun Rides on knobbies, it's simply a lot more fun to ride on the road with a MTB. i also have to say that urban riding on a MTB can be a last, Downtown LA for example is simply awesome and abundant with all types of obstasles and stuff to ride down on.
all i have to say is, ride what you want you want, wherever you want,and how you want; but you'll have more fun on a MTB

, no joke!!
this year i'll be doing:
Rosarito to Ensenada 50 mile fun ride (south of the border ride, too much fun)
Tour De Sewer 62 miler (fast ride that goes on 3 riverbeds: Rio Hondo, LA & San Gabriel)
LA Acura Bike Tour ~22 miles (ride with 15,000 other bikers on marathon route)
City of Angels Fun Ride 38 miles with an extra 6 mile option (very scenic)