Would you get>>>???

A 400 5.6l and a 70-200mm f4l or
a 70-200mm 2.8l non is and a 2x with a little $$$ left over //all used????
im going on a trip and will be shooting surfing and landscape....

Since it's all outdoors shooting you probably don't need the f/2.8 however since you will be travelling you probably won't want to be carrying arount 2 big L's. Go the 70-200 f/2.8 with TC. Amounts to the same focal as the 400 with easy composition adjustment (i.e zoom) plus you'll be able to use it indoors if you ever need to.

What about a 100-400L?

Either that or I'd definitely spring for the 70-200 2.8 + 1.4 TC idea.

I think you get better IQ out of the 70-200 (not sure about with the TC). Don't really like push-pulls myself.

mikeassk,
Like Woogie said, What about the 100-400L?
You get the reach, IS and it fits easier into a camera bag

I hated the 2x on my 70-200, so I would go with either the 100-400 or the 70-200/4 and 400. The 2 lens kit gets you slightly better IQ at the expense of convenience, so for travel I would probably lean toward the zoom. Of course since the 400 and 70-200 don't have any extending tubes (all internal movement on both) they might be a little better for shooting around sand, until you switch lenses of course. So, unless you have 2 bodies I would probably just get the zoom.

I'm with timbop, I didn't like my 70-200 f2.8 w/ a 2x TC. AF was painful(on my XTi), and the IS was inadequate for 400-mm. The drop off in IQ was noticeable, but not terrible. The 70-200 works VERY well with a 1.4 TC. I've seen posts from people that get excellent results with the 70-200 + 2x, it was just beyond my ability to hand-hold.

If you can deal with the "dust-pump", I'd look at the 100-400L.

The image quality of the 400 prime will be better than a 70-200 with a 2X converter. It has also been shown that a 400 prime is better IQ than a 100-400 Zoom at 400 mm.

As for sand while changing lenses one could use a changing bag, to minimize flying dirt if necessary. At least with a digital it would not need be opaque as did the old film changing bags.

WMS

Thanks for all the points guys and gals.
Thinking of just going with the 70-200mm 2.8 and 2xtc. I just got a 70-200mm port for my waterhousing so im set on that lens now.
I like the comfort of having a faster mid range zoom. That 100-400 is enticing though.