CyBorgQueen,

The mini pumps and similar sized pumps are great and necessary for on the road flat repairs. They work and they will inflate your tire to a proper PSI, assuming you have the strength.

BUT THEY ARE OBNOXIOUS! What takes me 5 or 6 "easy" pumps with my floor pump takes me...o....I don't even want to know how many...with my mini pump. My arms ache, I'm tired, I'm annoyed, etc.

CO2 solves that for me on the road, but cartridges are expensive. I'll gladly pay the $3.50 or so to get going again out on the road, but I'm not paying that once a week to top off my tire at home!

With a floor pump I can put more than just my forearm strength into it (more like my entire upper body), which means it's easier to pump AND I get more air per pump. Arms aren't tired, I'm not annoyed, and it takes no time at all.

That's nothing to do with MTB vs Road. I still have to carry my CO2 or mini pump when I'm on the mountain bike. And in fact, since my mountain tires are inflated to a much much lower PSI (30ish vs. 110) it's much easier to use a mini pump with the mountain bike and get reasonable results.

As for pricing. Pumps have different heads (the connectors) of different quality. More money buys you (at least in theory) better, easier connection, better seal, easier pumping, and longer lifetime. Some of the cheapies have a history of routinely breaking or being hard to get on and off the tube (whack your hand on a disk brake or your chainrings once when it comes flying off and you'll understand this HURTS!).