Here’s Mick’s answer to the difference between Chardonnay and Cabernet, dual DHT/6SN7 option aside:
As you know the law of diminishing returns applies here, its a bit hard to describe difference, but I’d say the Cabernets are just more pleasing , they have a bit more magic, stuff you don’t exactly “hear” but very satisfying. I’m very proud of the Chardonnay, because it sounds so good, and snubs its nose at the rip off prices of some of the junk out there. Its a simple uncomplicated design that delivers. The Cabernet is a little more complex that delivers a bit more, but is still very competitive price. I guess it comes down to want you want to spend, but you will be happy with either of them.