Although he is not my favorite painter, (I'm not sure I could settle on one), nor even my favorite cubist, (that would be Georges Braque), I have always enjoyed Gris' lively and somewhat disorienting compositions, his sometimes unusual sense of color, and his remarkable ability to convey texture. (I'd consider him the first real master of mixed media.) His paintings are seldom relaxing, often being remarkably energetic objects. The oldest of them were made more than 90 years ago, but still seem new. I've always felt that they capture and preserve the air of their time much better than do most photographs.
Update: The links to the large size pictures (the "color" and "texture" links) wouldn't work. Apparently, Webshots now denies access to those pages unless you reach them directly from one of their other pages. I've changed my links so they reach the smaller sized pictures, (and I hope Webshots hasn't forbidden that yet.) To see the large versions of the pictures, click on the "View Full Size" links below the smaller pictures on the Webshots pages.