I've owned a Chardonnay for going on three years, the latest Sachs for almost two years and a Cabernet 8SN7 for just a couple of months. The Cabernet and Chardonnay at this time are in different house in different systems in different states so haven't had a chance to do a side by side comparison yet. Going off of my experience with the Chardonnay versus the small time I've spent with the Cabernet my take on the differences between the two are that the Chardonnay is a smoother more comfortable classic tube sound while the Cabernet is a more lively sound more to the neutral side. I guess some people would say that equals more dynamic but it's just different. They are different circuit designs and as the Cabernet gets more hours on it some of it's characteristics may change slightly but don't think it will ever be as "warm" sounding as the Chardonnay. It will come down to what you are looking for and how you think it will fit with your current or future equipment. One clear advantage I have found though with both Supratek's over the Sachs is with the tubes. Tubes that are unacceptable to me in the Sachs in terms of noise play fine in the Supratek units. Also the options of either balanced or SE outputs and adjustable gain are an important factor to me as I tend to swap amps around.