I do pretty much exactly the same thing. I'm traveling extensively, and wanted a way to carry several bookshelves worth of computer manuals and resources along in a very small car.
After looking around, I wound up with an Irex Iliad. The model is a couple of years old. They might have newer versions. I also understand somebody has out an 8 1/2 x 11 model...
That being said, I love the device. I read mostly PDFs on it (I have a Safari account through work). I tend to sort the books on my laptop, and stick the card I want into the device (the Iliad will simultaneously accept an SD, MMC and a USB stick). I can look at the pdfs on the PC, too, if I needed to cut/paste, etc. Most tech books are formatted a bit bigger than the Iliad, so reading them as PDFs on it means they are at around 80% their normal size or so. I'd have to do the math, but I have no problems reading them. I have 20/20 vision, fwiw.
E-paper is much easier to read outdoors, and easier on your eyes. Personally, I like to wander out to the pool, and sit in the sun while I'm reading. That's practically impossible with a laptop.
Things I picked the Iliad for:
- It's Linux-based, and open source. That tends to mean that there will be community support for any open format. There's either native support or plugins for epub, pdf, html and every other format I've needed.
- It has a stylus, and lets you write persistent notes directly on the document (they're stored as an overlay file, along with the source doc in an XML wrapper.)
- It can connect/load via WiFi, from any normal WiFi hot spot (contrasted with the cellular access in the Kindle,
which won't work out-of-country. (edit: the kindle now has international cellular access))
- At the time I got it, it was a huge screen. It's no the biggest, anymore, but it's big enough for me to read comfortably (it also has options to switch into portrait mode, zoom in pages, etc, etc.)
- No Amazon-owned DRM. I wanted no part of that, two years ago, and my concerns have been substantiated over time.