I think the P4 is fantastic, so long as the traffic is flowing freely...used it yesterday morning to get to Brixton in 20 minutes. But I invariably cycle to work in Brixton and pity the passengers, sorry customers, stuck on a stationery P4 on Dulwich Common or through the Village. The south circular can be so unpredictable in the morning peak that you simply cannot predict if you will arive to timetable or an hour later! To me it's a no-brainer: the cycle is king apart from the odd very rare flat tyre you know exactly when you'll arrive at your destination. And it really doesn't rain that much...and my employer gives me a ?9.25 cycle allowance each month!