I paid for a non-flexible economy ticket LHR to lebanon and booked via BA.com and got another 10% off base fare for being a shareholder- I still found the flight cheaper later that day thro a consolidator

I went thro the online application- make sure you keep an e-copy of the better quote-save the page!

I went thro the performance- and got the feeling it was being managed by a no-so-great non-uk call centre type place- I called and made a huge fuss over the phone- got a refund to the better price and 10,000 BA miles for my trouble- worth it for me- but I would always try:

www.traveljungle.co.uk as a screen-scraper and consider www.expedia.co.uk for zero charge for credit cards incl amex