I remember when cubic zirconia became available and the excitement over having a diamond look alike for much less, though early prices were still quite high. Then CZ was supplanted by moissanite, and now by lab diamonds. At this point, it comes down to the high price of gold currently, and your own taste in the stones you want.

I like the zig zaggy look of this ring by UK firm Priya, made using cubic zirconia and gold plated stainless silver (great if you have skin sensitivity). It looks a lot like designs by Suzanne Kalan, but at USD$38, at a much lower price point. Great as a travel or just a fun ring.