Have used AB twice recently - for BHD-STN-VIE (return) in October and BHD-STN (return) in November. In October, both the outbound legs and both inbound legs were all but full on a 737-700. The same aircraft was rostered to do BHD-STN and also STN-VIE, and vice versa on the return flights. Offerings of ham or cheese rolls and a soft cold drink or tea/coffee were fine. Beer/wine etc were available for a price.
The aircraft were clean, tidy, and the crew uber efficient and pleasant. Comfort was fine (I need to use a walking stick for comfort and getting to a window seat is sometimes a tight and difficult task with some other locos), the atmosphere was comfortable and welcoming, though sitting on the apron in Belfast listening to the safety announcements in German is still a little odd.
Pre-allocated seating is a major bonus.
I'd have no hesitation in using them again. Let's hope they stay long on the Belfast route and can offer even more connections from their STN hub - Salzburg perhaps, if anyone at AB is reading???