OK, I'm a bit late coming to this thread, but I'd like to relate my experience with MD. I have a Sony JA555ES deck - the big gun, if you will, the one Sony ES went all out on (dual power supply, tank-like construction, no expenses spared parts, etc.) - a 30 pound monster that sounds absolutely gorgeous. The analogue converters on the line stage and the DA converters of this behemoth are second to none, and I mean really! I've never heard a DAT deck anywhere near this price range (the JA555ES retailed for around $1000 US back in 2000) or even double or triple that figure that even comes close to the quality that went into this machine.
The typical MD naysayers, meaning ill-informed "audiophiles" have probably never properly heard MD, period. And very few of them have really listened to a flagship deck like a JA20ES or (its successor) a JA555ES. Now these models feature a level of construction and DA conversion that will blow away most consumer (even the upper end) CD decks. Just as MD portables have noticeably better construction and higher quality output than PCDP's, so too do the Sony ES decks when compared to CD decks several notches above the ES price class (and that includes, strangely enough, the ES CD decks).
This is truly a case of getting what you pay for. The oft-touted "laid back" or "loss of presence" characteristic of MD is hardly at all apparent in a deck like this. Yes, I do occasionally (and I stress that it's exceedingly rare) detetct some minor difference in the MD recording and the original, but it's minor. And I think I or anyone else would be hard pressed to correctly identify which is which in a blind test.
This machine, in case you haven't already noticed, is one of my favorite pieces of equipment. (I also own several MD portables, so, yes, I do very much like this format!)
As for Hi-MD, I welcome it, but will also wait to see what happens. There's no great hurry for me to embrace it just yet. I hope the format does take off and that an ES Hi-MD deck will appear eventually.
One more thing about the advantage of MD. This is the only consumer audio format that writes to Magneto Optical disc - the longest-lasting and most stable digital storage medium there is. (Why do you think that medical records are stored on Magneto Optical and not CD-R/DVD-R or trusted to a harddrive?) Yes, a damaged MD (more often than not, usually attributed to TOC failure arising from subpar, offbrand blanks - anyone remember Hi-Space brand? Not to mention Memorex!) is a drag, and I've had approximately 3 out of well over 1500 die on me over the years. (Two were Memorex, one was Hi-Space.)
For every dead MD blank one can easily build a ramp to the moon out of dead CD-Rs!
One more great thing about this format: tired of the contents of any particular MD? Erase it and record again. No waste, no CD-R in the trash can - nothing! What a great concept!