Sony PCM-M10 will make you think long and hard about the future of MD recording.
Absolutely. From someone who has been into live recording since the release of the MZ-R50, having then owned the MZ-NH1 and then the MZ-RH1, moving on to the PCM-D50 and now recently the PCM-M10 definitely cements the idea that flash based recording is not such a bad thing as I once thought it was.
My motivation for sticking to MD (and more so HiMD later in life) was the fact that I had physical media for my masters and that was cheaper compared to having a whole stack of memory cards as masters instead. That and the MO media was no doubt more robust than memory cards. I wasn't overly concerned about swapping discs in the middle of a gig (of which I mastered the art with my MZ-R50, heheh) because when HiMD came around, I was happy to record in HiMD-SP mode with excellent results.
But with hard drives getting bigger and cheaper over the years, my opinion of storing the material was beginning to sway though I was not yet convinced. What did convince me, ultimately, was the day that a student apprentice dropped my MZ-RH1 which rendered the record head useless in it. That revealed the one last weakness of MD which I could not put up with again knowing that the MZ-RH1 was the most fragile unit in that aspect.
So it was out with the mechanical components to reduce the working parts down to purely electronic. I took the plunge while in Japan in June 2008, bought the PCM-D50 and haven't looked back since. Though a brick for taking into concerts, it served me extremely well and now with the PCM-M10, all my wishes have come true. Recording concerts in 24 bit mode really did give me noticeable improvements in the final result and that's something that I never would have seen with MD. Of course, it can only be of any real use if you use a decent set of mics with it.
I regret stocking up on all those HiMD discs. I must have around 50 blanks left over which I'll probably try to sell on eBay to clear out some drawer space.
So as was just previously advised, don't bother investing in a dead medium, get your hands on the PCM-M10 and then invest in a good set of mics. I've used the Core Sound binaurals (though pointing towards the stacks pinned on my collar spaced around 8 inches apart) for 11 years and only just recently decided to use Core Sound cardioids using the same 11 year old battery box.
My only hope is that when you finally decide on what mics to go for, if they happen to be Core Sound, Len won't take so long to get them out to you. My first experience with him back in 1998 was most pleasant and extremely rapid. I can't say the same for my second experience in 2009 as it took almost 8 weeks and no response to my emails or phone calls until I raised a PayPal dispute. Then I finally received them about two weeks thereafter. All is well and the mics perform superbly for the heavy metal and jazz gigs I so thoroughly enjoy reliving through my recordings.
I'm not sure what changed between 1998 and 2009 but that's the situation as it stands today. Those are my recommendations and that's my forewarning. Good luck!