I've previously replaced like-with-like. But you cannot get a 2009 rear wheel now anywhere. if I use a 2010 one will it be compatible with the brake? And is the diameter different (i.e would I need to replace both of the rear wheels? buggypitstop who are near me, will do the job for £80 approx, but they say that some sort of modification is needed to the brake, so £45 for 2 wheels + £36 labour charge. If I could just buy the wheels else where and fit them my self it will obviously be cheaper.