I am very impressed by the van and have no complaints at all about noise. I have never driven a VW Cali to compare as I wanted the MP from the moment I set eyes on it. My day to day car is a 9 year old Audi A8 that I have owned from "nearly new" and still runs like a dream. I have a place in Como and drove the A8 there in the summer. It is still a majestic motor and got me all the way from Glasgow to Luxembourg on one tank for a cheap refuel!
I have since taken the MP to Como twice. It is clearly a very different vehicle to drive, but I have absolutely no complaints and thoroughly enjoyed the journey, even though this involved driving for two days solid to get there in the shortest possible time. The van came with Continental Sport Contact tyres, but for my trip in November it was wearing a set of Continental TS 850's. Although I was not able to compare 'side by side' I did not feel there was any discernible difference in road noise and, based on the way you drive a van, in handling either. Was just glad to have them on when it started snowing driving through Switzerland!
I am not sure that the driving modes affect the suspension. I believe it is just the gear change characteristics. I mainly used Eco on the motorways as I am a tight Scotsman and want to eke out every last mile from the tank, but also because the fuel tank is much smaller on the MP than on the Audi. As soon as you get on to a road where there is more driving than 'cruising' or if the traffic is heavier, I would recommend going back to Comfort. I have not used Sport.
I am embarrassed to say my wife and I have only spent one night in the van so far, but we aim to sort this out over the summer months. It was supposed to arrive in July, but didn't get it 'til late October (no excuse I hear some of you say!). However, based on my experience of ownership of the vehicle as a long distance driver, I am delighted.