In regards to Andreos' post above (stupid Tapatalk app won't quote the post).

I ain't a massive fan of the E200, especially more recent ones, rode a Stephensons of Easingwold old style E200 66 plate on Moorsbus a few months back and the rattles and shaking of panels from the back of the bus was Irritating (even when the bus was in motion), also rode a Stagecoach Yorkshire E200 MMC on the 22x from Barnsley to Rotherham and it sounded like it was plagued with mice as it was squeaking pretty much constantly.

Although it wasn't the smoothest, I still thought E400 MMC 7544 which I had back to Newcastle offered a more comfortable ride than the StreetDeck I got from Durham to Newcastle on the GNE X21 (was quieter too). Video of 7544: https://youtu.be/vz3zyNkX6rI