my guess is color/looks, plus probably one will be for those of us who are a little poor and haven't gotten the epic riding skill, then the sweet ones that require the expensive cloth also require you to be 450 tailoring, and probably to have the epic riding skill; also might have to like specialize in one type of cloth like the spellweave/shadoweave/mooncloth from BC and by specializing, you might be able to use only that specialized type of flying carpet. Either way, I'm totally stoked for my lock to have a flying carpet