We fly SWA out of Providence frequently and Orlando (not as frequently). We've never had trouble getting seats together (even once traveling with a group of 5).
As a former frequent traveller both nationally and internationally, I don't have a problem with the SWA boarding pass way of doing business. I've been bumped and displaced even with a boarding pass from Northwest, American, United, and Continental so I know even a pre-printed boarding pass is no guarantee I'll be seated.
What I like best about SWA, besides the fares which are usually quite good, is the attitude of the staff, the cleanliness of the airplane, and the fact that in all the flights I've ever taken with them (probably up to about 40 over the past 3 years) we've taken off and arrived on time (sometimes arriving ahead of schedule) consistently. They've never lost my bags, I've never been bumped after paying for my slot, and they've been unfailing courteous and customer oriented on ever flight. In all my years of flying I can not say that of any other airline I've flown.