Picking Shapes for Shekeres

This year I made my first trip to a gourd farm to choose some gourds to make shekeres. It was somewhat difficult finding the right shape and size gourds, which brings me to my question: What sort of shapes and sizes do you use for shekeres?
It seems like we want three spherical gourds of increasing size for a guiro/bembe ensemble and a longer, somewhat tube shaped one for a rumba shekere. But what is optimal for neck size and opening size, as well as body circumference?
Also, how do you like to do beads? I already had one with three pony beads on each stitch, in both diagonal directions, so I ended up making one to match that, but of course there's many different ways.
Does anybody use glass beads or other types besides plastic? My Cuban friends made one with seeds and shells, which I suppose is very traditional, but its not particularly durable.
I've seen some great pictures posted on the shekere thread (in particular the ones by fidelseyeglasses and bongosnotbombs, both with two totally different aesthetic styles..), so I know we've got some killer craftsmen on the board.
All opinions are greatly appreciated!
It seems like we want three spherical gourds of increasing size for a guiro/bembe ensemble and a longer, somewhat tube shaped one for a rumba shekere. But what is optimal for neck size and opening size, as well as body circumference?
Also, how do you like to do beads? I already had one with three pony beads on each stitch, in both diagonal directions, so I ended up making one to match that, but of course there's many different ways.
Does anybody use glass beads or other types besides plastic? My Cuban friends made one with seeds and shells, which I suppose is very traditional, but its not particularly durable.
I've seen some great pictures posted on the shekere thread (in particular the ones by fidelseyeglasses and bongosnotbombs, both with two totally different aesthetic styles..), so I know we've got some killer craftsmen on the board.
All opinions are greatly appreciated!