I just looked at Z class for overseas flights, was toying with the idea that if I'm running short on miles for making elite, and I could swing the extra dollars to close the gap or completely make up for the delta in making elite, I'd actually consider the fare cost for Z to LHR from SFO since LHR is one of my favorites destinations. Is $3400 really a good deep discount unitedbusiness first rate? Or are there better ways for closing the gap or getting better prices on this kind of long haul flight in a premium cabin for better pricing?

Thanks!
Eric