It was challenging, now I am thinking. I just believed what TFL said: it takes 1hr 14min cycling my home to Hampton Court! In fact I took over 2hrs! Even though the scone in there was awful, I am very satisfied that I finished. I feel like I rode back from Paris.
Before I visited paris last year I researched everything about Velo. I think it is very efficient for visitors to travel in the city by bike. However I was too trepid on the deposit. I just gave a guide to french guys how to hire them but I didn't. Now London has a cycling scheme with a list of Do and Don't. Very last thing we should remember, cycle on the left!