(08 Jun 2014, 10:14 am)BJ10VUS wrote Yes, but look at the pollution levels in Beijing compared to somewhere like Newcastle or Middlesbrough. The fact of the matter is, with the new EU 'Euro 6' regulations, whatever new buses GNE buy for the TTX, they'll be 'green' whether you like it or not.
Also, while tri-axle vehicles would help with capacity, they'll be horrendous on fuel. Glasgow's Enviro 500s, for example, just drink diesel and it won't be good for a route that covers so many miles.
Glasgow's Enviro 500s are the old model. Alexander Dennis have since introduced a much updated version, which at Euro 6 should be better on fuel.