Telephoto lens suggestions?

[Scarecrow]

Never thought I'd put up a post like this, as I've always thought I knew my own mind and what I wanted, but I am dithering over a choice of lens.

I am looking to get a telephoto lens for use on a 5D2. In the past I have hired a 100-400 L and was quite impressed with it, so I thought that was going to be the lens I would buy.

However, I have just been reading a review that says they suffer from bearing problems that lock up the zoom mechanism, and if an extended warranty is offered, be sure to take it

So I thought, ok, what about the 400mm f/5.6 L prime. Unfortunately this lens isn't fitted with IS, which I feel might be of some use given the focal length. :shrug:

Then I considered the 300m f/4 L IS, which could always be used with a 1.4 extender, but I understand that the AF on this one can be a bit slow, which won't be any help to the weak (by modern standards) AF of the 5D2. :shake:

Now I'm going round in circles and am back to considering the 100-400 and a policy of keeping my fingers crosssed that nothing goes wrong if I buy one.

Anyone care to throw their thoughts in to the mix?

 

[Flamez]

Then I considered the 300m f/4 L IS, which could always be used with a 1.4 extender, but I understand that the AF on this one can be a bit slow, which won't be any help to the weak (by modern standards) AF of the 5D2.

I've seen it used photographing low level aircrafyt on a 7D. The af managed with panning and planes travelling at 500 mph lol. I think it is also sharper than the 100-400 but you pay the price of no zoom