You might want to look at
RV Consumer Group. They've been rating RVs for over 20+ years. While some folks don't place much stock in their evaluations, many do and their continued presence in the market is a testament to that fact. The price of membership is a pittance relative to the overall cost of RV ownership and IMO, well worth the data provided. Especially since all the new brochures applicable to most used units have long left the shelves. That accompanied by additional info gathered from actual owners' forums, if available, will be invaluable. Recognizing each buyer has a budget, the combination will be quite helpful in making a wise choice based on what you have to spend. Good luck.