I Flew Zoom from Gatwick to Montreal at Christmas this year and Ihave to say it was one of my better experiences flying internationally. The return flight left later than the regular airlines at 11pm and I was able to fall asleep during takeoff and awoke for breakfast which was standard food. The planes and staff were really nice, the inflight entertainment was 1 movie, you have to purchase your headphones, that sort of thing, butlike I said I was able to sleep (which was a first) so I found it great!
I would recomend Fly Zoom.
Also love the Maritimes as I went to University there. Loads to see, let me know if you're still loooking for sightseeing suggestions. One place you can't miss is the Bay of Fundy with the highest tides in the world!