I spent some time in London recently and I just want to say that I think London bicycle commuters are the most talented and courageous urban commuters that I have ever seen!

I know that I would certainly use flat, double-sided pedals if I rode there.

Have your considered "traditional" double-sided road bike pedals? I really like the MKS Sylvan Touring model. The MKS catalog contains quite a few other models you may wish to consider. Big plus for me, you can wear "normal" work shoes, too!