If handling is important, I'd strongly suggest finding a way of renting a similar unit, or taking a long test drive.
There are many variables. The weight loadings of various class Cs. Alignment settings. And (importantly) our individual response to various handling cues and feedback.
I've invested in heavy sway bars front and rear, and the rear Roadmaster track bar. I've basically come to peace with the handling-understand the limits. I simply drive within my limits -speed and total miles per day. Essentially I enjoy the overall package and accept the handling.
If handling is a very high priority, I'd surely suggest driving various chassis and picking the one you feel handles best. In my case there were other overriding priorities.
FWIW at times I can take corners at 5-10 MPH over advisory speed, particularly lower speed corners with good visibility. The handling is quite precise up to about 45 or 50 MPH. I would not, however, attempt to take a 60 MPH advisory at 70 MPH as the handling precision drops with speeds over 55 MPH. Wind, slope of road, and other factors contribute to less handling accuracy at high speeds. In general I do not keep up with most car traffic on mountain roads, and I try to accommodate their passing, or use pullouts.