Thank you for your comment!  You are absolutely right, 14 euros for wine of the quality of El Regajal Seleccion Especial is not expensive at all!  It has not gone up a lot in price in ten years!  When I first tried the Seleccion Especial around 2003/2004, it was not much lower in price...back then it was a premium price for a Vino de Madrid and even generally in much of Spain.  Fifteen years ago, El Regajal was really instrumental in changing the reputation of Vinos de Madrid, and was one of only a few.  Now there are many amazing wines but it still remains a benchmark wine.  I was definitely focusing on the wines of San Martin in this article and did not explain the prices in enough context...thanks for pointing that out.  I will of course be trying it again on my next visit to Madrid...I look forward to trying La Retama, which I have never tried.