Sprinter, depends on age.
1st Choice - True Auto
2nd Choice - SprintShift
You will usually find an Automatic Sprinter (Auto with Torque Converter) or SprintShift are quite well sort after.
The SprinShift is just a manual box with an extra gear and an Automatic clutch, drives okay.
SprintShift has now been dropped by Mercedes for the 2006>on Sprinter. They only have true autos or manual. The SprintShift has been handed down to VW's Crafter that Mercedes build for them and beeen re-branded "ShiftMatic".
On certain Mercedes True Automatics, the towing weight is limited to a mere 750kG. So beware if you want to tow a car or heavy trailer.
SprintShift is similar to what Fiat and Iveco have that they call "ComfortMatic" and "Agile", Renault's is called "QickShift 6"
Our is Mercedes is a SprintShift and we have had a lot of issues with it (including the Mercedes Technician not be able to start the because he did not realise that you had put the gearbox in Neutral by way of pressing the brake and side shifting the gear shift!).
Common dislike with the SprintShift is the very short 1st gear, designed as a kind of crawler gear. Jerky initial set off and gearchange from 1st - 2nd. Other than that when it is working it drives like a dream. If you have Mercedes Cruise control even better as not only can you change gear manualy without pressing a clutch or easing off the accelerator but the cruise does not cut out. In other words, if you are cruising at say 50, you can down or upshift manually.
Would I have another? I would try and avoid it and go for a true auto which narrows it down to Mercedes Sprinters.
Hope my advice helps?