Discovery vs Diplomate

I'm looking to get into a diesel RV after having a gas Bounder for three years. I've found Fleetwood Discoverys and Monaco Diplomates for around the same price, comperable year and mileage. We like the layout of the Discovery but have a feeling that the Monaco's are better quality. Does anyone have any experience or thoughts on this?
It there anything that we should look out for or stay away from for these coaches?