I haven't had a chance to update my own thread with my own finding but now that I have an opportunity here they are:
I wish I could report what others are saying but fact is that my 3880 does leave pizza wheel marks.
When I printed first few prints on gloss and semi-gloss paper I was ecstatic as I couldn't see them and was ready to call it a day. But then I re-read statements on 3800 FAQ page that were indicating they are visible only under certain lighting and from certain viewing directions.
So I went back and re-examined prints from all angles with magnifier under harshest light I could throw at them and sure enough, pizza wheel marks were there.
I wouldn't be able to see them 99.99% of the time under normal viewing conditions (like diffused light and normal viewing angles) but when examined under the sharp angle and high contrast light in direction of paper path I would see them.
They were most visible on glossy paper, less visible on semi-gloss, and very rare but still some of them there even on fine art paper.
I then tried already prescribed "remedies" and nothing change that. Changing of print speed did not make them go away. Nor did change of platen. No matter what I tried they remained there.
At that point in time I had to stop and ask myself what I should do as so many people were reporting no pizza wheel marks at all on their 3880's.
While mulling over that I remembered I had some of sample prints Epson sent me from their 3880. I went back, found one that was on semi-gloss paper, examined it carefully and lo and behold there were pizza wheel marks even on Epson's sample.
Sure they were in smaller amount than on mine but they were there and that was on printer that printed who knows how many pages so far while mine is brand new.
That made my decision making much easier. I have decided to stop wasting time chasing pizza wheel marks, as it was obvious even Epson's own prints have them, and to instead be pragmatic about them, minimizing them by avoiding high gloss paper when possible, ignoring them where I can do that (as they are not visible practically all the time under normal viewing conditions), and when I don't want to ignore them using paper path that does not result in them.
And as for question why my Epson and my copy have them while many claim theirs don't, I don't know the answer, and probably never will. It could be due to manufacturing tolerances and it could be that many didn't expect their prints as strictly as I did.
In any case I plan to have fun with my 3880.