I've played several and owned one -- briefly. None of them exactly curled my hair. OK entry-level guitars I suppose, and they can be had for cheap, but pretty unspectacular.
They didn't do a thing for me back in the '70s when they were new in the stores. I was busy checking out everything I could get my hands on, and they were just average when compared to other Japanese imports.
I agree with the above comments with two exceptions. There was a Madeira Jumbo Maple. Can't remember for sure the model but maybe P 600 or something like that. It was a fine sounding guitar and again reasonably peiced. I also had its Mahogany twin in the Jumbo body style. I have no idea of the model but it too sounded really big and full. I liked it.
Liked 'em both but not well enough to keep them so I guess that's telling. If I saw either of those two again I might pick them up though if the price was right.
My first two acoustics were Korean-made Madeiras - an A-12 (I think) which was an all-laminated mahogany dread with spruce top (in my avatar) and an A-22 (or maybe an A-18A) which was the matching 12-string. They served their purpose as "beginner" guitars for me. They weren't horrible, but they paled in comparison in every way to the US-made Guilds which I coveted at the time. The were trouble-free for the ~8 years I had them which was a plus.
My first guitar was an A-1 or A-2, not sure which, concert size, 80s or early 90s, probably made in Korea? I remember it as being somewhat hard to play and that it didn't sound great... of course, I was a beginner. I know I used to think my friend's Eterna, a budget Yamaha, was a high end guitar in comparison! But seems appropriate that my first guitar was in the Guild family, even if it was a poor substitute for the real thing. Anyway, I imagine that the earlier ones built in Japan were of a higher quality. They were not too cheap when adjusted to today's dollars, see this thread: