I've logged 4000 miles on a 2004 chopper, and 15,000 miles on a 06 K-9. I'm 5'10" 300 plus pounds and wear 30 inch inseam jeans. I think the Chopper outhandles the k9 with the shorter wheel base and 250 rear tire, especially if it is an 05 or later model with the slam primary. The drag bars on the chopper though had me leaning forward a bit too much for long trips. A 400 mile ride to Cookeville, TN was mot pleasant on the chopper. With drag bars, I just don't think my dimensions were quite right for that model.
The K9, oh man it fits me like a glove, I LOVE IT. She's a beast so you have to muscle her through turns sometimes, but proper form, proper air pressure in tires, looking in the direction of the turn, and a little elbow grease pushing those handlebars make it all manageable. The bike dispatches minor bumps in the road with no problem, but you will feel it if you hit anything moderate or severe. You will however want to customize the seat for longer trips if you weight a lot.
As for the Ridgeback, I test rode an 04 and almost bought an 06, but the dealer after looking at how many miles I was riding talked me out of it. I rode the ridgeback in an industrial area of St. Louis, lots of bumps, rail road crossings, etc. It didn't feel like anything I couldn't handle, and was surprisingly tame considering all of the stories about rigid bikes.
I have no experience with the other models in the big dog lineup, but that 07 bulldog catches my eye everytime I stop by the dealer.