Your figures are not far off from mine and the reason I upgraded to the Class 5 truck. The largest of these campers put a Class 3 over its RAWR when filled water and gear. Most of the Class 4 cab chassis trucks should handle these well, but I plan to tow heavy behind mine which required going up one more class.
Although I doubt you will have your fresh and waste tanks filled at the same time, these campers have more space and storage than the smaller models which will result in more personal items being carried.