Acceptable ISO from 5D2

Does anyone have a feel for the max ISO one should use for stock from the 5D2? Just in general term.

There has been a test that showed that following ISO's are almost equal in terms of noise: 160, 320, 640 and 1250 and all are better than the intermediate ISO's. And that's available for video mode only. The max ISO one should use depends on a lot of factors and there is no short answer - but the most important thing is the final image: there should be as less as possible noise. A bit higher noise is acceptable only for night shots - but 5DII behaves pretty nice even in that situation. Short version: use whatever ISO but check the final image on 100% for noise. Hope that helps.
Regards,
Christian

A very good answer, thank you.

I have seen reviews that state ISO of 160 is the best over-all, even better than 100. You should not have a visible problem with anything less than 640. Again the shutter speed and f/stop will make a big difference with any given ISO.

1250 is the one I never go over, and I haven't had anything rejected for noise from other agencies.