Flew them in November REP-PNH on their A321. Can't speak to business class, but no complaints in economy -- flight left more or less on time, still got water service on such a short flight, no charge for a checked bag, etc. All-in-all an uneventful trip.
My understanding is that all of their aircraft are relatively new and leased from Vietnam Airlines, which owns half of Cambodia Angkor Air.
Booked my flight directly on their website. It had some sort of warning about needing to show the credit card at check-in, but that wasn't enforced.