Here's my list, which may or may not be helpful:
Although there is a hint of American Oak on the palette, I was very impressed by the Charles Krug Yountville Selection Cab. It's at $26, which may be over your limit, but I found it very elegant and balanced.
For a little more money ($35 or so), I also like Clos Du Val's basic Cab bottling. The 2004 is a little "closed" and discombobulated at the moment, but I think it will be quite nice in a few months or a year or two.
If you have a BevMo and are willing to spend even more, they are running a special from a small, semi-cult producer in Stag's Leap-Vine Cliff 2003. It's a great Stag's Leap Cab that normally sells for $69, but is running for $39 and is worth it. A beautiful wine that is elegant, balanced, not sweet, and drinking well now with significant upside potential. I was very impressed!
In the same range ($32), and if you are willing or able to have it shipped, I am very impressed with the elegance of Tom Farella's wines:
http://www.farella.com/ourwine.html
Cheap and good, but pretty darn balanced the last time I tried it: "The Other Guys" (A Sebastiani label) Aquinas Cab is nice for $11.
The Sterling Napa Valley basic bottling o (Napa Valley, not the cheaper stuff, which is red grape juice, imo) is balanced, not too sweet, and has nice varietal character for $19.
...(Humans) are unique in our capacity to construct realities at utter odds with reality. Dogs dream and dolphins imagine, but only humans are deluded. –Jacob Bacharach