Agreed...what would you like to know about it?
The stars denote the grade of calfskin used in the head - the more stars, the higher the quality (in terms of more even thickness, color, absence of blemishes...)
From my own experience, quality doesn't much matter in an instrument that, in my opinion, sounds pretty horrible at its best (like a mandolin banjo) but I'm sure somebody loves them, somewhere.
I believe they originally hail from a brief period when the banjo was replacing the mandolin as the primary rhythm instrument in bands...so they thought a hybrid was a good idea (?)
The Slingerland company churned out far more inexpensive banjos than most...so much so that we used to joke in a certain banjo forum that, when asked what such and such a vintage banjo was, we'd say it was a Slingerland until proven otherwise.
The Maybelle moniker comes from "Mother" Maybelle Carter of the Carter Family.
Slingerland did make a vast line of banjos, many of which were higher line and more costly, but the Maybelle series like that one typically were mid level or lower.
That is not to say they were not well made. In fact, I would not be surprised that if you took the head off and looked beneath the tone hoop (most of which were made of steel, IIRC), you might find the pot was made with one thick ply of rock maple with thin veneers of more figured maple on the outside and inside. This when most makers were bending three or more plies of maple or some other wood to make a banjo pot.
As far as value is concerned...they're not all that much in demand - but a lot depends on the pot size since a lot of them are purchased for conversion into 5 string banjos. Most open back 5 string banjo players want a pot size that's 11" or bigger in diameter, in my experience of buying and selling vintage banjos...and lots of these mando banjos fall short of that diameter.
If I had one laying around, I'd see about setting it up as a banjo uke