I only received two sketches this past Saturday at NYCBM but both were great. One was by the well known George Perez. The other was by the much less known David Quiles. I've seen him many times at the NY shows I've gone but never got a piece from him until now. I asked for a character I only just discovered the evil Kryptonian goddess known as Cythonna and he did a bang up job on her.
His art style as you can see from my piece and his Deviantart page
http://davidquiles.deviantart.com/
focuses a lot on darkness giving a very silhouette like look or night look on his pieces. Just figured I'd show him off a bit. He's a great guy, does great pieces and on a pretty quick schedule and for not all that much either. He did my piece (on two sketchbook pages) in about one hour and 15 minutes.