Welcome to the forum. From the factory the MB chassis rides better than the other class C's chassis I have driven. Granted I haven't driven another class c in 5 years so newer Fords might be better. Cross wind and truck turbulence handling can be improved with suspension mods. Hopefully MB has improved on the emission issues. None so far on my 2016 Melbourne but several on 2013 Sprinter van (same engine). Only MB issues so far have been 4 wheel speed sensors fail all at different times. Nearest MB dealer is about 1.5 hours away but fixed under warranty. Routine maintenance on the chassis side is more expensive but the diesel engine does take about 13 qts of synthetic oil and you do want to stick with recommended fluids. Service intervals on my 2016 was every 20k miles but I stick with the 10k interval like on my 2013 van. Expect to pay about $200-300 for a oil change and inspection.
Jayco craftmanship (fit and finish) on my rig isn't the greatest. The Melbourne Prestige might be better and wasn't around when I bought mine. At the time I bought mine the price was $30-40k list cheaper than " higher quality" rigs. I had a few Jayco warranty fixes and the process and experience was better than I expected. If you get one with a folding mattress see if it is like the one in the following thread.
https://www.jaycoowners.com/forums/f...ess-49622.html
If it is you will have issues with it and I would be disappointed they haven't addressed the problem. Might give you a bargaining chip to get a better mattress. The mattress is a queen size in width but only 76" long. At 6'4" I made it work until we had the issue like in the above thread. I now use a 80" long standard queen mattress and sleep like I was at home. Road noise off the lot was terrible but after several mods it can be made better.
Good luck with your search.