Since you are including the '03 in your search, you are looking at 2 totally different trucks; '02 up 1500 and '03 up 2500 & 3500 are the new body style. The new body is in fact a completely new truck and worth the price of admission over the previous (not that there's anything wrong with those).
The trans problems you've probably heard about were on the lighter duty models with the V-6 and V-8, so this shouldn't affect your buying choice of the diesel model, plus there probably aren't any left that haven't been rebuilt/updated. I've been told that the problem transmissions are restricted to the pre-merger years when Chrysler/GM were co-oping transmissions.(pre '98?)
I have an '02 1500 quad-cab with just a tick over 40K on the clock and it's been flawless. I've towed the Porsche across country on a U-Haul car carrier (about 6000# combined) and had no problem hitting 100mph across Wyoming in mid-July; it tows well.
Compare to the Toyo, it's gonna be alot more "truckish", but since you've already driven one I guess you know that.
www.dodgetalk.com is a BBS like this that can get you tons of info on the specific years/models.