The 1989 CW II was original, so I believe it has the K-52-K mid driver, which is also the same driver that is in my 1983 CW's. I can't really put my finger on it, but the difference was huge. Unfortunately, the CW II's sold just a couple of days ago, so I won't be able to investigate any further. I will be installing Dave's Fastrac's, along with ALK's Universals in my CW's very shortly. I just placed the orders within the past couple of days and can't wait!
It has been quite an adventure recently, with four sets of Klipsch in house. I had two sets of Cornwalls, Quartets and RF-7 II's all occupying space in my living room at the same time. You will be happy to hear that the upgraded Quartets are my favorite of the bunch. I recently installed Crites crossovers in the Quartets as the final piece of the puzzle. They sound AMAZING. I will see how the upgraded CW's compare when I finally get upgrades completed on those. They are almost as good as the Quartets now, so I can only imagine how great they will be when completed. The RF-7 II is also a very nice speaker, but is definitely a distant third, and maybe just a hair better than the CW II's I had. The RF-7 II's are up for sale now as well...