Once again. Just go to your friendly neighborhood bicycle shops and ride all of their touring bikes.
Check out Fuji Touring...the Trek 520...the Marin Four Corners...the Raleigh Clubman...and the Surly's.
If you still can't make up your mind, then just take the Trek 620 off the bike peddler's hands. Tell 'em to knock thirty bucks off and you'll pay him fifty bucks to install new handlebars, tires, and a new seat. Additionally, you won't purchase a bike that hasn't been properly lubed all 'round. That means the BB, the headset, and the hubs.
Good Luck!
- Slim
PS.
Since he already agreed to the tires, you'll just have to spring for the seat and handlebars. He should have lubed the other stuff anyway if he's a legit bike peddler.