It is a very hard decision. You didn't say if you were thinking used or new. We have a Monaco product that we are very happy with but I don't know that I would buy a NEW Monaco/Holiday Rambler at the present time while they are being bought out/restructuring.
Just remember that all brands have some nice models and some entry level models. Try to find out where the one you are looking at falls in the available models for a manufacturer.
If I were looking for a used 40 foot Diesel Pusher, I think I would look at Monaco Knight, Diplomat or higher; Holiday Rambler Endeavor; Newmar Dutch Star or higher, Winnebago/Itasca; or Phaeton. I haven't seen anything in the Fleetwood line that we liked at the same price point although their higher end models are very nice.
I would look for something 2006 or newer if possible because that is around when the interior heights were raised and the advent of the one piece windshield.
Floorplan is very important but as it is your first motorhome it will be difficult for you to know what you like. Try to imagine yourselves living in the coach for a month - where would you each sit to watch TV on rainy days, where would you put your groceries and/or dishes. Outside - where would you store your grill and lawn chairs, bottled water or beer/sodas. The outside storage bays can look really large until you start putting things in them - then they fill up really fast.
Cargo carrying capacity is a very important factor if you plan to be in the coach for any extended period of time. Think of it as the equivalent of the foot print of a new home construction. You can't add carrying capacity later, it has to be there from the start.
Good luck in your search.
Dave & Kathy
2007 Monaco Knight 40PDQ towing 2018 Ford F-150 & 2017 Harley Trike
Fulltime 2007 to 2016, now halftimers
Before you give someone a piece of your mind, make sure you can get by with what will be left.
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