Re: Non-ceramic Bobbins
Most or today's bobbin holders will accommodate a wide variety of material spools by simply adjusting the arms to it them. The only thread spool they don't fit is the old gudebrod skinny spools. The height of spools from different manufacturers doesn't vary the much if at all.
Poor quality materials and tools are destined to discourage beginner tiers and cause greater expense when the time comes to replace them.