We weren't impressed with Allegiant for anything other than price, and like they say, you get what you pay for!
It was really just the staff we weren't impressed with. They were very unprofessional in my opinion. Boarding was a nightmare - they didn't enforce people boarding by zones - when they called the 1st boarding zone hordes of people in all zones rushed the gate, I guess in hopes of stashing their carry-ons so they wouldn't have to pay to check them. I would have been livid had I paid for preferred boarding & had to wait in a huge line of people that had not paid for it, but were getting on board before me. They were gate-checking carry-ons til we got on, the overheads were full.
Boarding info was slim to none - we had a delay (NOT Allegiant's fault) that started at 30 min. & progressed to over 2 hours - 1st there was a medical emergency on the incoming flight that they had to take care of, then there was ice that delayed us. No information was announced, and I guess they really don't have to announce anything, but no one knew what was going on & there was no one even at the gate area to check with. I found that frustrating considering it was an evening flight. It was just myself & 2 DSs, and we just waited....and waited....and waited....with no updates from Allegiant as to what was going on, or when we would depart.
Once on board the staff was indifferent, no welcomes, smiles or thank you's for anything. One of our seats was occupied & they wouldn't move when I showed them our boarding passes with that seat number. I kindly asked the FA to double check the boarding pass for me & she shrugged & said "whoever is right gets the seat" and walked away.
Once we landed in MCO (at 12:15am!) they blasted the song "Move It" through the loud speaker system, and an FA came on & said "come on people, we want to get out of here too, let's go." I thought that was rude. That was the only communication the entire flight. We never saw a FA the whole time either (there are no snacks on Allegiant).
Would I fly them again for the cheap price? Yes. We got the seats for $39.99 one way (about $60 each with taxes) so it was a good deal. I guess I just had my expectations set too high on the quality of their staff!