Baldman, if you are aiming at the Tablet PC for your mission critical stuff (good idea, IMO--it's robust and while it doesn't have the pros of e-Ink, it also doesn't have the many cons of e-Ink), then what are you looking for in a reader? Just an e-Ink screen and cheapness?
That's what I was shooting for, and for me (in the US), the best e-Ink screen + price combo was the Sony 505. I was tempted with the 700, but when I revisited my main points: "e-Ink screen", "cheap"...I realized it would be a bit hypocritical to get a model with a less-nice screen AND a 33% higher price. As for why I went Sony instead of some other perfectly good brands, I'd guess it had a lot to do with local brick and mortar availability. There's a Sony Style store that's a short hop away for me via mass transit.
Although the PDF support (DRM + reflow) factored in as well. I brought an SD card into the store to carry out some tests before buying, and was reasonably satisfied with my results.