Hi Raife, Tough time to be looking for an RV...coming out of the 2008 recession, the RV industry has seen its longest-ever streak of sales growth and prosperity. They thought the party was over when COVID hit, but the most recent edition of RV Business has interviews with industry leaders talking about how demand is thru the roof and nobody can run hard enough to keep up. Dealer inventory is at an all time low and delivery times are double what they normally would be.
That said, all 3 of these TTs look to be a good match with your size/weight range. These are a much better fit with your Durango and should provide you with a good towing experience.
The Grand Design looks nice and they make a nice trailer. The Gulf Stream has no outside kitchen but is also 600 lbs lighter. Sadly all the specs on the Jayco are TBD on their website. Both the GS and GD have good tank sizes for their overall size.
I would plan a day to look at all 3, see how the floorplan "feels", decide whether you like the outside kitchen, etc., and of course price. If you find one you like and the price is right I would buy it if you want to get into a TT this year. If you're not in a hurry, then I would wait until the spring when dealer inventory catches up with demand and you'll see good deals again at the spring round of RV shows.