Well, I'm a Mosaic loving person. I feel they present a quality product, and that they do have a consistent format and structure to their releases. At this time I think they serve beginning collectors more than seasoned ones in a number of ways. Seasoned collectors will likely have a nice mixed media collection of one of the artists Mosaic may tie into a nice cd packet. A new collector can get all these in one whack with little to no duplication; a seasoned collector will weigh the cost of a set against the fact that a lot of the material already exists in his collection and play the speculation game as to whether what is remaining may appear on the parent label as a single release. . . .That can be a hard process for us old fart collectors to go through unscathed.
Although I can see P.D.'s point better expressed elsewhere that Mosaic may be releasing material that is not quite the jazziest or the very best of an artist, I do think a lot of this is based on personal opinion (and a lot of the selected artists to feature are based on personal opinion of the producers I'd wager) and looks different to a collector with one decade or less under their belt than the collector with two or three or more. . . .
Anyway, I've really been excited about the direction into the music of the thirties and forties that Mosaic has taken, and those are the only sets I have preordered in the last few years or bought immediately!