The 2009 PRO+ is basically the 2008 2.4 SL with a few minor changes. They use the same axle & flange distance as the 08's. The 09 weighs 466 grams (+40 to 50 grams) and I would assume this is because they ditched the carbon window and it now looks like a metal hub. The PRO+ does have the ANT+ SPORT. Those are the only differences.