Northwood offers the same good warranty service that GD or any other 'Good Warranty Service' MFG does. They will set you up with an independent repair shop if a dealer isn't nearby. You can call NW's tech service department anytime. If you don't get thru they will always call you back. BTDT.
The 29-5T will need a 1 ton to pull it. They are heavier than the other's because of the way they're built.
We are going in to our 5th camping season with our NW 5th wheel. After a couple very small fixes it's been trouble free. for the last 3 years.
My suggestion would be to go and look at how the drawers are put together on all 3. Look at how the frame gussets are welded in at spring hanger areas.
Look to see how thick the baggage doors are. Is there any OSB used anywhere instead of plywood?
Of all 3 why does the 29-5T have the highest GVWR of 15,700 lb? using the same tires as the others? Stonger frame.
I would take a bed slide out over a fixed bed any day.
Fiberglass rear cap and 8'6" wider on the NW
Go to the Northwood MFG web site and then to their Facebook page. There's a couple photos of how the roof is made. They glue and screw 3/8" plywood down on thicker roof trusses. Most don't glue and just use staples. You can see that the insulation is the same thickness clear out to the edges. Not tapered down to nothing as you get to the edge of the roof like others do.
Lots of little things are the reason the AF costs more and weighs more. May not be as glitzy because the glitz money is spent on better construction materials and methods.