We have been struggling with Regent air. The phone wait times are frustrating.
Just to compare, I checked the internet to see what Princess would charge for LAX-LHR in May business class. They listed many possible flights and I chose a KLM flight for $3,070 round trip non-stop business class. I could even pick my seats before committing to the cruise. I did this in about 5 minutes on the Princess website. If only Regent was as good as Princess in making the air reservations!