Yes, all of the Alpenlites are now orphans :( But if you're looking for a TC from this era (2004-2009) then none of them would have any factory warranty remaining anyway.
My Saratoga 935 comes in right at 4000lbs loaded (note: I don't have the Onan gen'). If you're gonna haul this thing on a SRW truck then you will need a 350/3500 and you should seriously be considering 19.5" wheels and tires.
I think that the 935 has the very best floor-plan of any shortbed camper I have ever seen, period… and it is more spacious inside than some longbed TC's. My family of 4 travels in ours and it never feels cramped (for a TC, that is). In terms of storage, I would say that the 935 is "average". However with just a little bit of work it can made to have
plenty of space for all of your stuff. I'm happy to share photos if you need storage ideas.
The Center of Balance is 39", measuring forward from the rear of the tuck bed (not "up").
I haven't had any issues with my slide-out, but it is certainly something to think about if you're planning an extended trip through S. America. At the very least you should become proficient in how to operate it if the drive mechanism should ever fail.
Here's a
link to the 2007 Alpenlite Truck Camper brochure.Cheers,
-Mark