Would you say that the screen of the Onyx is much better than the Kindle Touch?
I am in your situation. I read a lot of pdfs for hours at a time, but I don't work on them like you do.
I just need a good reader, but I am loathe to invest 350€ on an M92, inasmuch as I don't know who they are and it seems that the quality of the stuff depends on the goodwill of the vendor and I don't really understand who does what. There are so many vendors each with its own branding, firmware and support. And pricing.
I could possibly invest 250€ in an Amazon product (a new DX for instance, but I doubt that Amazon will come up with this type of product any more), but being a conservative type I just need belt and braces before spending the price of a week in a 4 stars hotel in Thailand on unknown quantities.
Thanks for your time.