The Pilot III sounds like the one for me, usually I instinctively go for the most expensive one but on this occasion I'll opt for the smaller/cheaper one.
Has anyone got a Pilot for sale in the Surrey area? I could look on eBay I suppose but I'd prefer to buy a second hand one (if I can locate one) from someone "I know". Failing that, Keef - could you bring yours to Duxford for me to have a play with?