While is it not exceedingly difficult to find decent wine under $15, it is indeed rare to find in this range really great wine. Even more rare is great wine made from 100% Napa Valley juice (it only has to be 85% to legally pass as Napa Valley which is how many producers cut costs) that costs less than $50. Wall Cellars 2005 Cabernet Sauvignon (90 pts., Available at Longhorn Liquors $13.99), made by the ultra-boutique Vinoce Vineyards located on Mt. Veeder in the Napa Valley, is truly the exception to these rules.
A nose of plums, tobacco, spicy oak and crushed fall leaves leads to intense and focused red and black fruits supported by rich, chewy tannins that carry several layers of complex, smoky flavors. This is what the Napa Valley is known for; big dusty/earthy fruits with velvety-rich texture and weight, superb concentration and exceptional varietal character. This is what is known as Terroir (tear-wah), or the particular flavors and aromas imparted into a wine by the overall combination of climate, microclimate, soil composition, microbial life, etc. All the things from beginning to end that are indicative of a particular region or vineyard.
As wine from California, as in many other parts of the world, need contain only 75% of the listed varietal to be labeled as such, about 85-90% of all wines from these regions are blends. One consequence of this practice is the dilution of terroir, which is why many Americans are not familiar with this term nor with the importance of it.
The concept of terroir is why we have legendary wine regions across the world, where their particular geography supersede the varietals they use, such as Chianti, Bordeaux, Burgundy, Rioja, etc. This is the spirit of wine making, to illustrate the complex relationship between the vine and its earth, and the way in which it is expressed, as an extension of the land and not just a product of it.