We have an Axis, and we actually think it's quieter than our former Class C Sprinter. We do have a squeak coming from somewhere near the windshield bottom on the passenger side, but I usually forget about and stop noticing it. Hopefully, we'll be able to figure than one out. It is a comfortable ride, as well.
It does seem that there are far more complaints about the Ace than the Axis. Apparently, they come from different factories?
The one thing I have noticed, noise-wise, is that the furnace on the Axis is the loudest we have ever had. I've not seen anyone else mention this, so perhaps it is just our unit.
All in all, we are really loving our Axis and have had very few issues.