I'm still using my M92 with the original firmware it came with when I bought it just after the device came out. I suppose some things have changed since then, although I wouldn't know which things.
It has worked fine, although I've only used it for reading, not for scribbling in texts -still haven't found out how to do that- and many of my books ended up in different places like "Downloads", "My Books" and just on the "Internal Storage" page. I wouldn't mind having them all on one page or on one list. Now I often have to look for them in different places.
Many books I see only the name of the author of instead of the title. I would prefer to see the titles of the books. Especially since I sometimes don't remember what book the name of an author is referring to.
I still think this Onyx M92 is the best looking e-reader I've seen, all white with just a thin silver line as encasing, and just a few minimal white buttons. It looks great. And I love the big 9.7" screen with excellent sharp definition/contrast easy readable texts.