I am keen on wildlife photography and due to my treating myself with a new gadget every time I got a new contract ended up with both 500mm f4 and 600mm f4 lenses. I almost never use them though because of their weight. My friends who take pictures at Grands Prix carry one or the other all day, goodness knows how, I only even took them if what I was photographing was near a road!No, quite the opposite. I seem to be having a lot of problems conveying my thoughts without annoying people today. Amir is a strong proponent of using really great gear for wildlife (among other things) photography and has a stellar collection of lenses. He has cost me a lot of money by nudging me toward better equipment. I think you will find that he, and many of us, are kindred spirits.
Apparently I need to insert the joke thingie more often.
Eventually I tried a 4/3 camera and found the picture quality better than I expected. Now I have an Olympus micro 4/3 with 300mm f4 and a 1.4 converter that I can easily carry all day and the 600mm f4 has gone. The biggest difference on actual pictures is the difference in depth of field, which is often an advantage with the smaller sensor.