Not track use, but the 309 is what I'm solely using. Only comfort I'm missing is RCL. Got some ebay kit to install at some point. 
Probs does 50-80 miles a week maybe.
Noticed the rear axle is failing now though.
	
	
	
Probs does 50-80 miles a week maybe.
Noticed the rear axle is failing now though.

 
 

