We owned a 2005 Chinook Concourse with the layout you describe. Build quality is very good. The area you need to watch for leaks is the rear door design (changed in 2003), the rear storage compartment door seals and the fridge vent on the sidewall. View one on a rainy day if you get a chance. The sidewall angles in slightly in the design by the fridge vent and water can hit the platform that the fridge sits on. On my model it had a plastic tub and drains at the fridge platform and the rear storage compartment to divert any water away. You can easily add peel and stick RV gutter for added insurance at the rear hatch, fridge vent, and top of the rear door. In my case the only water that ever appeared was at the rear step in a heavy storm. Gutter above the door eliminated the issue.
There are different trim levels on the Chinook. Concourse is the top of the line in the shortest models and the dead giveaway are the trapezoidal side windows. Premier is the next level down with rectangular windows. The Eagle is the bottom end and I wasn't happy with the quality of cabinetry. Bigger versions are the Cascade or Destiny. 2 feet longer and 6 inches wider. The Glacier is on the 450 chassis and has a slide. The Summit is the largest one they produced.
We recently transitioned to a 2008 Winnebago view 24H. The reason? A family of 4 in a Chinook Concourse was just too tight. It was much more viable for 2 people. The change meant moving from 2 feet, 8 inches longer. Width of the View is actually slightly narrower than the Chinook.
We still use the View for day trips and camping. It is great for both. We like being able to have 2 kids go to bed in the small cabover while we can stay up for a bit longer and the small slide has made a big difference room when we are together. Narrow is helpful for parking. The build quality and materials are not up to a Chinook but the added space has more than made up for the difference. The view has a fiberglass roof and cap and filon sides. Leak risks are at the skylights and of course as with any other RV, vents, TV antenna, etc. There are also models with storage over the cab instead of a bunk. I considered a Born Free but it was out of our price range.
Here are the possible leak areas to watch on the chinook. You will see the gutter I installed above the door for added measure.