I'm taking a trip at the end of this month for some birding here in Texas. I'm renting the lens, and so far I can't decide if I want to rent the 100-400L or the 400 5.6L. I've rented the 400 5.6L in the past and loved it. I'm just wondering if limiting myself to 400mm only is a wise choice.
I have a 24-70L and 70-200 and shooting with a 40d.





