I am looking to purchase a telephoto lens and I'm torn between the two. They are both near equal in terms of cost. However, looking over the specifications of both I know the L is better optically than the non-L series lens(L is sharper wide open, and has better IQ). That aside, would the extra 100mm be worth it? Does anyone have both lenses, or have tried both? I have read nothing but good things for both so I am torn.

I plan on doing more nature photography and sports due to my son now joining soccer.

I have an APS-C camera(60D) and will be upgrading to the 5DMrk3 next year so both lenses I know will work.

 

Any thoughts or opinions?