I have the first gen, which is nowhere near as fast as LCD. But looking at their videos it looks like they got the framerate to work at a much faster speed than mine which was leagues of improvement over a kindle. However, I'm confident that there will still be some lag between input and what you see.

They wrote their own software so that the display isn't doing a hard refresh every time the display changes, the downside is there is some ghosting, which is what the hard refresh on kindles will remove.

I use keyboard shortcuts extensively to the point where I rarely use a mouse so I can work with the low framerate of the first gen. It even forced me to get better with using keyboard shortcuts and now I have little to no problems with it.