I'm pretty sure 2012 and 2013 have the same geometry. For the XL (58) Horizontal top tube is 565 while for the XXL (60) it's 577. But you also are more upright on the XXL -- the head tube on the XXL is 220 while for the XL it's 200. I suspect it comes down to personal preference. If you could actually get on both an XL and XXL you could probably get a feel pretty quickly. I guess the trend is to go with a smaller frame, but I think you are gong to find a bit more saddle to bar drop on the XL which may not be to your preference given this is an "endurance" bike. Note that my XXL came with 30 mm of spacers under the stem so I could drop it a bit if I need to (I think I would have to go with a shorter stem though).
scott s.
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