Hi,...
Minidisc is a dead format, but it still has it's fans.
There are numerous and varied handheld portable Minidisc recorders that do a decent job of live-to-stereo recording. Most of the vintage Minidisc machines have what's called "ATRAC" data compression. It's a "lossy" compression scheme a lot like MP3. ATRAC was the bain and Achilles heel of the Minidisc format for many people. Other people, like myself, think the ATRAC encoding is pretty transparent. There are also "console" style home Minidisc decks, which also use ATRAC. The standard Minidisc media is pretty affordable.
The real shining examples of Minidisc format recording is the Tascam 564 and Yamaha MD4/MD8 multitrackers, however, they use a harder-to-find Data-Minidisc 140Mb. These are really fine multitrackers, and the media is still available, but it's more expensive than standard MD media.
The latest generation of Minidisc was a big improvement, with Hi-MD. Hi-MD can handle a number of compressed data formats, including ATRAC and MP3, but it also extends it's range to include handling standard "16/44.1" PCM data format. However, these only come in a handheld portable (Walkman) style recorder, not a console style home deck (or multitracker). The Hi-MD disc media is a bit more expensive than standard MD, but is not as expensive as Data-Minidiscs. This highly useful and progressive upgrade from standard MD to Hi-MD was not good or soon enough to save the format from inevitable obsolescence.
Still, tho' not in the US, the Minidisc format is still going a lot stronger in Japan and non-US countries abroad, (or so I've heard).
If you don't mind investing in a dead or nearly-dead obsolete format, MD is a pretty good performer. The MD8 or 564 can be had used for pennies on the dollar, and the vintage designs of these units give a lot more flexibility than most more modern CD-compatible multitrackers,... namely having the advantage of a premium analog mixing section.
The Hi-MD portable recorders seem to be a good product & is suitable for many purposes.
Either way,...
Good luck!
/DA