You can check in on-line 24 hours before flight time & get seat assignment/print out boarding passes.
We switched from USAir a few years ago because of their financial woes & AT's lower prices.
For a
budget carrier, they're not too bad. We've had a couple problems:
1) Lost luggage issue (which they initially denied, then recanted when luggage was found @ another customer's house a month later). Of course, we're enjoying our comp'd tixs

.
2) They fiddle with departures out of MCO quite a bit w/o always sending an email notification (although they insist every reservation gets one).
Despite the negative issues, we've signed up for rewards program (enjoyed the Wendy's cup flight vouchers) and also got one of their CC's that I'm earning miles on monthly (and paying off monthly).
Still, I'm awaiting a Ding SW fare for June & will cancel scheduled flights/vouchers if one becomes available. We had to work our June travel around blackout dates & I really didn't want to shorten our trip.
Good luck.