We love the Southwest Chase Visa. At the beginning, we signed up for two cards at 50,000 bonus points each. (One in each of our names. In hindsight, I should have tried harder to get two in one name so we could go for companion status that first year. I tried for a business card in DH's name but was declined and didn't pursue it.) We closed DH's card so we could concentrate on earning points in just one account. DH charges a majority of his business expenses on the card so we earn 3000 or more points a month on purchases. A couple of years later I got another one with 50,000 bonus points, and upgraded one for some more bonus points they were offering. Between those bonus points, points for purchases, anniversary points, and points from e-Rewards, we have flown for free for 4 years in a row now (4 round trip tickets each time). The last time I got bonus points, we managed to qualify for companion status, so this year DH's ticket didn't cost me any points. I have enough already to fly again next year, but I'd like to save them for the following year. I don't plan on applying for any more cards, so we won't be able to continue flying on points every year, but probably every other year.
It's been well worth the annual fees for us. A typical set of 4 round trip flights for us runs about $800-1000, so we've gotten $3-4000 of free flights. Not to mention the added bonus that if your flights go down, you can get points added back to your account to be used at any time, rather than a credit that has to be used in a short time (which we would never get done). That is awesome.