My experiences with Sprinters have been much the same as the others. I had a '05 2500 long tall that I ran 9x,xxx miles on in a little less than 5 years as a plumbing truck. It had a steady stream of issues with drive shaft, glow plugs, turbo, back doors cracking and rusting, etc., etc. And that's not to mention that after five years running it mostly short run, city driving, loaded heavy, the suspension was crying uncle.
Fast forward to 2010. My boss came to the conclusion that the old Sprinter wasn't going to hold up much longer. So we started looking for a replacement for it. I was unwilling to go back into a regular size van. He looked at cube vans, but they are difficult to get into tight driveways and lack traction in the snowy WI winters. So we settled on a new 2010 Sprinter 3500 long tall with heavy duty rear end. I've been driving this truck for 4 years now and have had many of the same problems with this one. Every 3 months or so, I have to schedule a down day to drive the truck to the dealer to have them fix whatever broke this time. Particularly, glow plugs and glow plug modules. The dealer finally found a melted wire shorting out on a heat shield behind the turbo about 4 months ago. We thought that was the magic fix, but about 3 weeks ago the glow plugs started acting up for about the 6th time. I will readily admit, running plumbing service calls is very hard on any truck. But my 2 Sprinters have had more problems than any of the Chevys or Fords in our fleet. The hassle is compounded by the lack of Sprinter dealers. No one else is efficient at servicing the thing.
For my last three personal vehicles I've had an '06, '08, and an '11 E-350 Super Duty Wagon. They were OK for hauling the kids and doing some occasional work out of, but now that I don't have to haul the kids as much, the seats were getting in the way. Being 6' 3" tall, and having gotten used to the height of my company trucks, I decided I wanted to replace the E-series with a tall cargo van. Being a Ford guy, I wanted a transit. Once the transit dimensions were announced, I gave up on that idea because they don't make one that I can stand up in and still fit in the drive through at lunch time. I don't know what the Ford engineers were thinking, but they should have taken a closer look at Sprinter and PM to see what dimensions they should aim for.
So I started weighing Sprinter vs. PM. Sprinter was a known quantity for me. I didn't feel that my personal use would tear up a Sprinter nearly as much as my work use does. But the Sprinter price point was more than my budget would allow. I had a real hard time when considering a PM. First off, I like American made things. The whole idea of an Italian designed, Mexican built cargo van with the running gear out of a Dodge Caravan was more than I could wrap my head around. After several test drives, my concerns subsided and I concluded that the PM should be more than adequate for my personal van. I ordered a 159" 2500 granite crystal in mid May, got it in mid August. I have built some shelving in the back for tools etc. There are some little oddities with the PM, but nothing that would be worth spending the additional money for a Sprinter. I still wonder myself though, how the PM would hold up to the use I would give it at work. Would it haul 4,000+ lbs. of cargo day-in and day-out? Or would it have all the minor mechanical issues a sprinter has and more? My gut feeling is that the Sprinter is still stronger built when used under a constant heavy load. I likely won't ever get a PM for work use because my boss has what we'll call a strong distaste for Chrysler. He is a Ford guy too, so in a couple years, my next company truck will likely be a Transit 350 long tall. I won't be able to get it through the drive through for lunch, but I'm sure my boss won't think it's a big deal.

For anything less than extreme duty use, PM may be the perfect option. So far, I have to say I am very happy with my purchase.