References:

Keystones are my favorite American barrels. The oak integrates well and is not overpowering, with characteristics of butterscotch, spice and sweetness.
- Pete Hedges - Hedges Cellars, Washington

I use them in all my high-end projects. Keystones are not aggressive as are most American barrels; they add richness to my wines but are not woody.
- Dave Corey - Core Wines, Santa Maria, CA

We've been using Keystone American oak barrels at Deerfield Ranch Winery for many years with great success in several blends, including in particular Zinfandel, Syrah, and Cabernet. I learned long ago that it is not simply the source of the wood or the tightness of the grain that counts but how long the wood is air-dried, the care in selection of the stave wood and toasting techniques. These factors relate to the cooper, not the wood. We now buy barrels according to who made them, not where they are made. With this in mind, Keystone and their commitment to quality and tradition remain my favorite American cooper.
- Robert Rex - Winemaker and managing partner, Deerfield Ranch Winery, Kenwood, CA

Pennsylvania oak, but with a French twist. Nice rich vanilla, but never overpowers or becomes high-toned. Opens up the mouth feel without making the wine heavy. Jeff Cohn, winemaker, owner JC Cellars.
- Review of Keystone Cooperage barrels, published in Wine Business Monthly