Jack:
yikes, your one-hand option only has to be even more challenging!! Had a friend when I was a kid who lost his left arm from just above the elbow in Korea but the guy could do ANYTHING one handed, including whip my rear end just to tease me....hehehehe...I always remember Frank when my pain gets me too down as I can never get away from it anymore and only have it getting worse over time to look forward to...d'oh!!
Makes sense when you mention using the GDX upside down...for me in the "normal" position the Kindle keyboards have always sort of just disappeared, which did surprise me with my K1 as I did not think it would become so transparent. But for some reason I simply cannot get comfy doing the 180-degree thing and have the keys on top...I honestly have tried. I suspect it has something to do with my constant hand fidgeting and well, knowing I have the option not to use it in that orientation causes me to sort of give up early on the effort.
I suspect I would be OK with the DX family as they exist because as many have pointed out it's a two handed device...and since learning of the silly lack of numbers on the K3 I know if I was to buy a reader today it would probably be the GDX simply because it's not horrible expensive, though not inexpensive either, and it also has the nifty new screen and will eventually have the even niftier (is that even a word??? hehehe) new PDF handling.
As far as buying a DXG right now, I would say no because I want to see where it all shakes out this year. I want and have a need for a large format reader/device but nice as the DXG might be, it's not 100% where I would like it to be so why not wait is my position...and maybe my point. If I had a more pressing need and the content was more widely out there in the area of content I most need/want it could be an option to compromise and "learn to love the bomb" but right now I am not in that situation, yet.