Price wise, it's a brgain for sure. I even accidentally used some 192a GH when it was sold to me as generic 191a GH & it worked way better than Jins. However, in the long run, it's not worth the possible problems that it may cause. Serno is the best, however, I will never use it due to the extreme prices. If I could be 100% sure that a generic was 191a, I'd stock up & never come off. But you can't test for this kind of thing & it's not worth the risk to me.