Don't know about comparison to IO or WP, but I have to say the screen is both better and worse than I expected.
I bought one to use mainly as a wireless web pad for surfing, e-mail, etc., and was hoping to use it as a digital picture frame (with slide-show screen saver or somesuch) when off-duty, but the screen quality rules out the latter. Only being able to display 4K colors really doesn't do justice to any of my digital photos.
On the other hand, whatever 4k colors this screen is capable of displaying must be optimized for the web, because most web pages I've browsed really look pretty good. Also, although I thought I'd get tired of scrolling around web pages designed for 800X600 or higher res, thankfully most of the web pages I visit with any frequency appear to have been created by competent web designers, who know how to scale for the viewer's settings.
One thing I am impressed with is the outdoor readability - the Stylistic's screen is much easier to read while sitting outside than my ThinkPad 600's TFT. Still disappears somewhat in direct sunlight, but in the shade under my lemon tree I can see everything just fine.
All in all, everything is relative, and considering what I paid for this I'm extremely happy. Thanks again Ryan!