Hi all. My first post, so please be gentle.
It's my belief that the various changes in NH-14WM labelling were just to do with capacity: 1400mAh, 1350mAh etc.
As for fakes, well I did buy some from a guy in the UK which were obvious fakes, and undoubtedly from a batch imported from Hong Kong or the likes. Not just the round cap on the positive terminal, rather than a round-cornered square or rectangle, or the obviously sub-standard plastic wrapper, but also the fact that they were at least 1.5mm too long and would not physically fit into the battery compartment of an R55, N710, R91 etc!
My experience with 'probable' fakes is that they self-discharge very quickly, and have a much shorter life than the 'real deal'.
Incidentally, Stephen, your comments on the MZ-NF810 are interesting. I recently put together an N710 package I sold (as you know, the N710 and NF810 are basically the same machine). As the customer was a regular, I decided to do him a special package and supply the NH-14WM battery instead of the NH-9WM which originally shipped with the N710. I had just given the battery a full test, and it came out at well over 1400mAh capacity. To my astonishment, the battery would not work in the N710. When attempting to charge from the mains adapter alone, the display would not even show the 'charging' symbol. When placed in the charging cradle, the machine just gave a slight noise, waited two seconds, gave the same noise, and repeated this process until power was removed (as an aside, the noise is of the overwrite head load motor resetting, which always happens at 'power on' to ensure the lid is not in the locked position).
Naturally I assumed this was a fault on the recorder, so I tried another. Same problem. And the same was seen with another four N710 machines. And yet, an NH-9WM that I had also just tested recently, again to its full capacity (900mAh), worked perfectly in every one of these machines. Since coming across this phenomenon I have not had time to investigate further, but there's obviously something not quite right here! I would be interested to hear of your experiences with charging these gumsticks, and any adjustments made to improve performance. Such as why the N710 is so finicky?