Bucketjr, the current model of the K&K uses a pair of 6H23P (the Russian 6922 equivalent). The differences in the basic vs. Maxxed-out K&K are rather significant, and the website illustrates the differences quite clearly. That said, I find my Maxxed-out K&K delightful, and have heard it against some fairly lofty competitors without feeling a huge desire to change, especially considering the price difference. YMMV.
-Richard
-Richard