@all thx for you responses and the welcomes!

@Andy I use a 5DMKII but upgrading to a 1D X soon. But all FF for sure.

@HDnitehawk: great comment. I think that is pretty much what I hoped for. The 300 or the 400 are those I am leaning towards. And probably 300 is good enough for most of the apllications I have. And for the rare wildlife occasions a TC will do just fine. The 400 is to mich of a beast for me. The pros should try to tame her but not me!

So the 300 it is. I'll just wait for the 1D X to arrive and than I am going to post some impressions of this combo!

Cheers
Chris