Using passes on SWA is easy as long as you know when to do it and when not to.
My family has done around 50 segments in the past year, and we have gotten stuck twice, both times in Vegas. The key to doing it, just like anywhere else, is waking up early and being flexible. Having such a huge domestic network means that you can almost always eventually get to where you are going the same day. Most of our CSAs are really good and willing to help. My wife traveled with 4 kids on December 23rd from OKC to MCO a couple of years ago nonrev. She had to do 3 legs to get there, but they made it.
If I absolutely need to be anywhere, though, I buy a ticket. No brainer.