I was just doing a web search and came upon this site. I sent them my dates and destinations (SEA-BCN and MAD-SEA) and they came back with a total for 2 people that is at least $1000 less per person. They have gotten decent reviews (although also horrible reviews) from people. I would love to book through them, but am very wary about 3rd party sites.

If you haven't used them, do you know of any other sites that would be good to use for business class seats?