The companion program you can use once per year (as I recall). You get 2 tickets for the price of 1 (but the one is more expensive than you could normally get) - as described.

The $50 off I mentioned is separate - it is unlimited and as long as you purchase the tickets through Spirit Incentives. May not be $50, but somewhere in that ballpark ($25-$50).

I don't know if you can earn flight points against the bonus points (search some other threads - I'm sure that has been answered somewhere). I signed up about 5 years ago, and at that time you could get flight points against the bonus points. For some reason I think I read that is no longer the case. I've never worried too much since I have more spend than flight points each year.

Huge bonus of the card in my eyes is that when you travel on 'reward' tickets, you acrue ff miles that also qualify for elite status because you are flying on a purchased ticket. With an airline cc, you don't get miles when you fly on an award ticket.

Good luck - enjoy the card!