I have generally found the pumps that I have owned pretty reliable and easy to repair on the road if something does go wrong.

CO2 has a few of serious disadvantages when touring. It is OK as a backup, but I wouldn't bother.
1. It is limited in capacity to the number of cartridges you carry. On a long tour you will need a lot of cartridges to keep tires topped up.
2. CO2 permeates through tubes much faster than air so tires lose pressure much faster, making item 1 an even bigger issue.
3. I don't think you can fly with CO2 cartridges (someone correct me is this is inaccurate). Since I tend to fly to my tour locations that is a hassle.

They are great for a quick tire repair though. I use them around town on my road bike, but don't use them on tour.

Oh yeah, to the OP, the Mountain Morph is nice and sounds like it would fit your needs pretty well.