I agree with Lindy. It's amazing how over the years, and the tons of debates from us "stoners", how the suppliers have evolved their "grading" systems to fit what we THINK we want. When I started this in 2007, there were A & B Chineses stones, Korean stones, DMC Machine Cut Stones & Imitation Swavorsky. Now we reportedly have several grades in each category
Just like the "green glue" or the "gray glue" and which is better. I don't buy all this grading hocus pocus and feel it's just a ploy by a lot of suppliers to charge more bucks. I buy Korean I stones from a supplier I've been using for years, no grading, no changes in quality. I like the shine and the quality and hopefully they will continue to provide good stones.
With the recent craze in the new "color change" stones, I bought some from my supplier and some from several other sites, forum members included. You get all kinds of labels like DMC, GEM Cut, Premium Korean, Premium Machine Cut, AAAA Chinese, etc, but the bottom line is I did not see a bit of difference in any of the ones with the very expensive names and prices from the KOREAN stones from my supplier.
I think with everyone jumping on the bling bandwagon, the BEST thing to do is to test out suppliers until you find one you trust and whos product you like. If you need to go a step further, do some designs in several of the various qualities of stones and go to your customers like I did. Ask them to choose the design with the best bling, then give them pricing for each design and ask them again which one they would purchase
In my testing, an overwhelming majority went for the Korean stones (I labeled them good bling/good pricing). Several people actually asked if the samples included Swavorski, which they did, but not a one of those people could pick out the Swavorski design.
Marketing and hype, along with brand name will fuel this craze, but if you provide your customers with an effective, efficient, reliable alternative, they will most often take that choice.