I'm thinking of taking a trip to Portugal in the Spring of 2015. I'd like to fly Premium Economy but tickets are more than double the cost of an Coach flight. Is P/E (additional 5 inches of space) really worth the $4,000 price tag or is flying Coach for 15 hours from San Francisco to Porto adequate? I suspect it would depend in the airline and configuration of the aircraft, but I thought I'd ask anyway.
p.s. I've read most of the travel tips and they are very helpful -:)