I have to agree with the others on this, Get it loaded and weighed and adjust the air pressures.
Most of the discussions here and on other forums pertain to the Ford Based Class C and their handling and suspension problems.
The Chevy cutaway has an excellent reputation for good handling /driveability with out modification, as others have said.
After doing a lot of research here and on other Forums I have not found that the Chevy Based Class C have any problems in this regard
The clickable thread in my signature,
Chevy Based Class C has some discussion about this as well as other things that may be helpful.
Good luck on your new purchase and let us know how you like that Chevy Based Class C.