Difference between ROAD and MTN Topeak Morph Mini Pumps

I am looking at buying a Topeak Morph Mini-Pump to use with both my road bike and mountain bike. I realize the MTN version of the pump has a lower PSI rating (guage reads to 110 PSI), but it is also smaller in size than the road version.

My tires only inflate to 110 on my road bike (I have 650s) and I have a small bike (43cm), so the smaller size is attractive to me. What I am wondering is will there be a major difference in function between the road morph and the mountain morph? In other words, will it be harder to fill up my road tire with the MTN pump because the max is lower?

Would I be better off getting the road pump with the higher PSI rating and just mounting it on my top tube somewhere?

I looked at the Zefal HPX, too, but am not sure that one will fit on my seat tube, since it's so short. I'm also having a hard time finding places selling the Zefal. Anyway, feedback is appreciated. Thanks!

One major difference is that the Road Morph has a built in pressure gauge. I don't believe the Mountain Morph does. I use my Road Morph on the MTB - no problem.