Sigma 18-200 OS: auto-focus at f6.3?

I'm hitting Central Europe next summer. I intend to travel light, so my kit will include the 10D, the 50/f1.8, and a decent walkaround (I'm not looking for absolute pro quality here). I've been looking at the new Sigma 18-200 3.5-6.3 OS, which looks like a viable option, especially now that there's stabilization. However, I've been reading all these things about the harmful effects of f6.3 on auto-focus. Some questions:

Does this affect the 10D?
If so, how much of a problem could this be in normal, reasonably well-lit situations (I've got the 50mm for when the light gets low-ish)?
At what focal length could I expect the lens to hit f6.3?

Thanks.

I've got the Sigma 18-200 and swore I would never sell it. I go hiking in the mountains sometimes and I usually take it and my rebel xt because of the weight. Both theirs and mine.

If you've got any kind of light outdoors at all focus is not a problem. I don't have the OS version so I can't vow for it although it should be the same.

Mine goes to 6.3 at the very end of the zoom I think around 170MM.

Side note: You'll love this as a walk around lens and if you stay around f8 you'll get some really sharp pictures.

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toteemi wrote in post #2528719
I've been looking at the new Sigma 18-200 3.5-6.3 OS, which looks like a viable option, especially now that there's stabilization.

Is this lens shipping yet?

Don't worry about the f6.3 effecting auto focus as it is wide open during the focus procedure. Lenses don't stop down until focus is achieved and the shutter is fully depressed.

crn3371 wrote in post #2531508
Don't worry about the f6.3 effecting auto focus as it is wide open during the focus procedure. Lenses don't stop down until focus is achieved and the shutter is fully depressed.

you see, the thing is w/ non-pro bodies, the slowest aperture you can af with is f/5.6. but i guess like the bigma, sigma has managed to deceive the camera to af.