Thanks for the responses everyone. I am confused since I love both my diamond studs and my moissy rings, and I definitely do not consider my moissy rings set in wg as costume jewelry. To me, costume will be cz set in silver.
I will not purchase now, will continue saving for another year or a year and a half and then decide. What is bothering me from yesterday is the opportunity cost, as compared to a 500usd pair for a moissy pair, the similar pair in diamond costs 4k. Thats a lot of money to me.
Another thing to consider is whether there's any other jewelry you'll want in the future that doesn't have a moissanite "equivalent." I recently made a big (for me) purchase of a Tiffany diamond flower pendant. The design is really unique (I spent months examining every single diamond/diamond-equivalent flower pendant I could find), and so it was really that or nothing for me. Studs aren't like that; if you want the "look," you have choices.