Make's you wonder about what exactly?
I personally hate working out of anything other than a W700, but many of the 700's online just aren't full anymore any it doesn't make sense to keep using such a large vehicle when it's not necessary. Sprinters get get better mileage and are large enough for many routes, also don't have to worry as much about fitting under awnings etc. This may not be a big issue in the wide open expanses of TX, but in larger cities it's a big deal having a smaller vehicle that can go/fit more places. The new 700's are subject to the same diesel regulations as the sprinters are, so that is really a non-issue. They will also have the filters/urea requirements. I don't know about your station, but the only thing our mx seems to do is change oil, do PM's, and change tires. Any real work on the motor/transmission gets taken care of by someone else most of the time......and since they are new, they will be under warranty and serviced by the manufacturer if anything serious arises. Also, they will not be rendered undriveable if they run out of the urea, they just won't meet emissions standards.
I dislike sprinters as much as anyone, but for the most part it makes sense. I wish we would purchase the dually versions though, they would be more stable and better in the snow. Some routes still need 700/900's, but not nearly as many as days past.