You won't find any decent tool shops in central London you will have to go out to the suburbs. There's loads on the outskirts of London just check on www.festool.co.uk they are all listed
You might be able to find a few tools there. They might even be wearing dark blue and green.
Maybe, some diamond encrusted Festools...?!?
Oh, I know!! A TSC 55 signed by the Becks!! Sold!! (Just not to me).
If you are headed to Mayfair enjoy it for what's it's known for. Posh life and decent restaurants. When I head to London, my company puts me up in the jw Marriott Grosvenor House on Hyde park. Very nice place. Enjoy your stay!!