Well I will see if I can get one to rent. I know the primes kick ass in the IQ area but are always so expensive and have little versatlity. there are always trade offs. I also have the 70-200 and thought about getting a 1.4x TC. I may still if I keep it. I am going to be interested to see how it does on your T2i. You may have gloom there but it is still an amazing looking country. Hope to visit sometime.
you have the right idea no angle, my decision was made much easier by the 400mm 5.6 thread actually, there are some stunning examples there, and the knowledge that the prime is sharper made it much to hard for me to choose the 100-400, (i also already had 70-200 covered and own a 1.4x.) I'm gonna take it out tomorrow in gloomy ireland and see what kinda joy it brings me on a 5D and a 550D.
that is good to know that it is not too awkward. the 100-400 feels like a boat anchor on the end of the T2i.lol Not having the IS scares me a bit since I like the ability to use the expensive 70-200 in many light conditions. Makes me feel like I am getting my money out of it in use. I know some lenses just have to be relegated to sunshine duty though for those perfect shots. I am still going back and forth with getting a 7D over a new lens. THe AF in it is what I want also. Why oh why couldn't I of been born into some rich Oil family?lol
You would love the 400 f5.6. Its so easy to hand hold. I'll start a new post tonight when I get home. I'll post some of my hand held shots from my kayak this summer.