BHO member @Noah Cline is making some. You can hear and see him in several videos. I have a Robert Browder Gourdeous gourd banjo and it's fun to play with its unique and earthy sound. My favorite recordings are from Adam Hurt's Earth Tones CD. Talk about good tone and skillful, lovely playing....
There is much info on them, here and elsewhere. I've been making and playing them for quite a while and love them; there are gourdies on all my CDs. The other reason I love them is that I have always encouraged players to build at least one banjo themselves. It will give you a feeling of accomplishment, a deeper appreciation of the instrument, and open up an entirely new vision of the banjo world. The gourd banjo is the perfect launching pad for your exploration. Curt Bouterse
re: durability, I've had a Thornburg gourd for over 15 years. No case, left out to suffer through wild changes in humidity, played frequently... and it's as good as new. I did have to change the gut strings. Once.
like others above, I love the sound, and it's only going to come from a gourd.
I find it surprisingly physically comfortable relative to an openback, too.