I'd go XLR if you are looking to stay with a SRW truck. I specifically started investigating XLR's due to their lighter pin weights than their competition with the same floor plan. Not only are XLR's listed weights lighter on the pin due to forward axle placement, they also are VERY accurate on their weights. My 395's dry pin is listed at 2647. Loaded and ready to camp with the garage empty it is at 2850#. Load the garage and it goes down to 2650#. All well within a SRW 350's specs. I am under on my truck's GVWR, tire rating, and RAWR. The only number you can't fight with a SRW is GCWR.
On the 2500 vs. SRW 3500 deal, the current generation Ram is a completely different setup between the two. Ford on the other hand is identical when comparing a 250 to SRW 350.
As to service after the sale, I can't say enough about XLR. They have been outstanding in every way. I did have a Keystone product two trailers back and can't say the same but that was 5 years ago with a different division so it's not an apples to apples comparison. If you decide to go XLR, do yourself a favor and shop Jeff Couch's RV Nation in OH. They were an 800 mile trip for me but beat my local dealer by $9500. You can always try to get your local dealer to come close to Couch's price first but mine wouldn't return my calls after I gave them Couch's number. They have a great build and price setup on their website where you can select all your options and get a no haggle price that's over 35% off MSRP. We are too fussy to take one off the lot and loved the big discount on an ordered rig. If you have any questions about XLR or Couch's, please feel free to PM me anytime.