I think I should tell the outcome of my story, maybe someone is interested to hear it.
I've seen the ColorFoto AF accuracy tests, too, like Thomas mentioned. So the experiences I made myself during my tests are somehow confirmed or at least, they sound familiar. As predicted, I sent it back for a refund because while the possible optical performance is probably the best on the market below 1000€, for me this can't compensate unreliability. But I haven't had a lot of luck with 3rd party lenses so far anyway.
That last fact could explain the decision I made a few days ago: I take my chances with a brand new Nikon AF-D 80-200mm F2.8. It arrived just three hours ago, so I'll pick it up after work - it's been sent to my parents so there's someone to receive the parcel, the company used DPD for shipping which do not deliver to parcel stations (those are run by DHL company). Oh, if Mr. Laing is watching this thread - I bought it in the UK, thank goes to the british crown
Reason was the result of the technical discussion I had with myself.
- It's discontinued, it's production has been stopped - but it has been the professional coice for over a decade, so while it's performance will be lower than the one of the new 70-200mm VR, it won't be bad. The problem of availability was solved, I found one new at stock.
- it suffers from near field focus problems at 200mm. But the issue is weaker at shorter focal lenghts + it starts to "disappear" while stopping down (it's actually rather compensated by other effects than disappearing, but you know what I mean), which for semi-macro work is necessary anyway. The smallest object I'm probably going to capture at 200mm/F2.8 from time to time is a face/portrait, so about 50cm in space if you include some free space around. That would make it necessary to keep a distance to the object significantly larger than the near field at which the problem occurs. In addition, if one keeps the focus limit switch activated all time, "extreme" near field focusing is deactivated and the danger to take shots in suboptimal lens performance range is reduced.
- I was guessing that "wide open performance at 200mm is also not up to todays standard, although it isn't that bad, probably like the sigma, maybe a bit better.". However I've seen ecellent performace of this lenson a D3 on flickr, so maybe it's pixel density dependent. This way, I'll have good cards using my S5pro, which I always use in 6MP mode. S5pro users know why.
- AF speed with limiter switch activated it pretty fast, although it relies on an internal AF motor. And best of all: it's confirmed to be spot on and very sure.
I'll give a final comment on this matter when I hold it in my hands.