The CC Showcase Yakima Valley Riesling is hands down my favorite white of all that I've made to date. I just bottled my third kit of this wine; decided to age in glass carboy for 6.5 month prior to bottling (the first two kits I'd bottled without aging), and it was wonderful at bottling. It is resting now, and I will try it in a few weeks once it settles down again.
I still have a few bottles left of my second kit. I'd heard of a wine going through phases as it ages, and I did see that occur with this wine. My first kit was consumed in less than a year, and it was wonderful at every stage. With the second kit, a bottle that I opened at about 1 year had a bitterness to it that I hadn't detected before; it was drinkable, but did not taste at all like Riesling and I was quite disappointed...enough so that I'd decided that I'd always try to consume this wine in under one year. I tried another bottle from that second kit at 14 1/2 months and it was like a completely different wine. It had lost the bitterness, and had a beautiful complex flavor profile and much more body than ever before. It did develop a more off-dry flavor, whereas it had been dry in prior tasting (and I do prefer dry), but it was pretty amazing. Moral of the story, as with most of the upper end kit wines, is to always save a few bottles for aging. In this case, I am very, very pleased.
Am really looking forward to the future of my third kit!