From what I know the greys have always been fine. It's the blacks that had mixed reviews. I used them for a bit but the last batch came tinted yellow and I stopped using them after that which was a few months ago. In Canada we only get the blacks so I've never tried the greys.
I used a few boxes of the Opti greys last year. I liked them! I think they were 12 IU vials. Quality seemed good and shipping was super quick!! I also had read that some of the QC issues were with the black tops.