1. Whichever carrier goes non-stop, or to a convenient airport. El Al isn't my idea of a 'fun' flight, if you're not Jewish they give you the frigging Spanish Inquisition, but years ago they had a direct service STN-JFK, which I used a lot. I lived 20 minutes from STN at the time...
2. BA or VS; not much to choose in economy. But if you get lucky and get upgraded... BA Club is better than many carriers First...
3. If you have to choose a US carrier, CO are about the best in my experience.
I've been practically commuting EWR-GLA for the last year, and CO have been just fine. Even if they weren't I'd still have to fly them as no-one else flies that route... non-stop is what matters!
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