I'm quite picky about stitch markers. I like them to have no joins, to start with. Anything with a jump ring is out; they always get caught on my yarn or knitting, and I'd rather just use stray bits of yarn tied into loops. Split rings are okay, as they have a lesser tendency to snag. But my preference for both aesthetics and performance are markers with wires that have been twisted into a loop. Ones that look like gorgeous earrings are a bonus.
They're surprisingly hard to find. Maybe I just don't use the right search keywords or something. But I did find some pretty ones at this Etsy shop, Tiger Eyess. After a series of pleasant and professional convos, she made me these custom markers as goodies for my yarn club:
Sue does beautiful work and is a lovely person to boot. Highly recommended!