After a few weeks loan of the 3880 from Epson UK, I've written up a review with my thoughts on using the printer
SP3880 reviewCompared to the 3800 I looked at a while ago, I'd say it was a bit more reliable in loading thick paper, but it did take a while to get the knack for perfect feeding.
If I had a lightly used 3800 I would not rush out and get one, but would certainly suggest that people thinking of getting a 2880 (which I looked at a few months ago) should think seriously about the 3880.
There are print improvements over the 3800, but without careful checking, and with 'natural' images I'd be hard put to point them out to most people in a blind test. I always remember from selling prints, that people who buy them don't check dither patterns with a loupe ;-)
Hope there are some aspects of the article of interest...