Originally Posted by
Roger
Are you comparing like with like?
I thought that £526 looked good value for two tickets. Without knowing your dates, I went into united.com and chose random dates in January. It came up with £276.20 each with a note that 'Additional taxes & fees apply'. Selecting that fare, I got: 'We are unable to retrieve fare information at this time. Please try again later.'

So I don't know what the all in price from UA would be.
For those random dates, expedia.co.uk offers a UA fare for two of £723.08, made up of £290.08 for the tickets and £433 for taxes and fees.
The point is that your Airmiles booking includes taxes and fees while the United web fare doesn't.
Whichever is best for you depends on your own preferences. Given that LON-NYC costs 10,000 Airmiles for two, I'd say that 11,000 from MAN was reasonable.
I must have been mis-reading the price quoted on the AA website - and not noticed that it was excluding taxes.