I currently have a 2010 Cannondale Six (Aluminum frame). I’m interested in upgrading the wheelset after hearing lots about the potential benefits. The bike currently has a set of Mavic Ksyrium Equippe wheels. Approximately how much would have to be spent to see a significant difference. I’ve been looking at a few ‘slightly used’ sets e.g. Ksyrium Elite/SL. Can anyone recommend a good wheelset which would represent a real improvement from my current set-up for upto £500?