There are a bunch of free software solutions for downloading from your jb3. They are much better than the original software and they do not typically require specific versions of windows.
Though it was shaped kinda funky, the jb3 was a pretty amazing recorder. Dual batteries, bit perfect opti in, extremely reliable. All in, what was it, 2001?
It's been ages since I ran a jb3, so I can't say for certain but I suspect you're going to get a really major improvement in audio quality from the m10.
Order some non-permanent screen protection film for it. If you put it on as soon as you remove the original screen cover, there shouldn't be any scratches or bubbles and it will adhere really well. It helps to practice on other devices.