Agree wholeheartedly about 7cm ties. I can go either 8 or 9cm, slightly prefer 9.
I can't wait until it gets a little cooler, then I will feel more comfortable breaking out the unicorn prints from last F/W!
Malford of London is a great place for ties and squares. I have a local shop, Samuel Parker in Baltimore, that has a good selelction of Drakes squares, for some reason, all he carries is the 7cm ties though.