The slide issue isn't solely Thor's black eye. Any brand with the schwintek system is subject to the same woes if it isn't cut and installed perfectly and even then it's under-engineered. I've read a few posts on Forza issues with the same system. They all have gone to a triple rail design. To me it's a bit of a Band-Aid instead of fixing the real issues. But if it works I guess the end result is the same.
If I were looking at entry level DP's I would throw a few others in the ring (in no particular order):
-Winnie Forza
-Newmar Ventana LE (Rv direct is selling these now)
-FR Charleston
-FW Excursion (they finally moved away from the black furniture)
-Coachmen Cross Country (the new 404RB has a salon bunk, best bunk design I have seen thus far)
I had my head settled on the Palazzo as the best bang for your buck, but after some of the stories I have heard and having friends that own one, I would strongly consider other brands. Shame, of all of them the Palazzo has the best floorplan designs and décor. And after owning a Thor I question it's quality. I love my ACE, but it is what it is - about as entry level as it gets. I expect concessions in quality for what I paid, I wouldn't be so forgiving if it were a DP I paid 2x as much for. Most owners still love them, but look hard at other offerings. All that said, in my personal experience after owning 2 Thors, they have some of the best customer service I have ever had with any product. That means a lot.