Are Frontier's award tiers fairly similar to the YX45 and YX50?

25,000 Standard domesitc award
45,000 Choice domesitc award
50,000 Last Seat Available award (Ascent & Summit members only)

I'm not a F9 member yet (figured it would be more hassle to combined accounts rather than move YX directly over) but at least for the higher-level FF members there is still last-seat-available award for 50k.

Until not long ago (last year?), Midwest's last-seat-available award was only open to Executive level flyers. If that's how Frontier does it, it goes back to how it used to be on Midwest, although it's easier now to get elite status than it used to be, too (20 segements versus 25 to get Executive in the past).

Does anybody know specifically the difference between Standard and Choice?