ahrma, I also spent some time on the Sprinter forum, was a good site. As I recall many were posting about the dreaded transmission rumble, if ours had it we never noticed the issue. Perhaps we were the exception but the I 5 was the finest engine we have ever owned. The only problems we had was the steering hydraulic cylinder went, $1,200 and as, mentioned we lost the blower ; turned out to be the vacuum control for the turbo failed-both of these were covered under warranty.
The only issue I have heard of with the year you had was with the brakes, and as I understand the problem was solved when MB went with larger wheels.
Ours was one amazing van, oil analysis always came back with metal wear levels so low that the lab would comment on what an exceptional engine it was.