Most of my distaste has been from a Samsung DLP that I bought around a year ago. It was pretty much DOA, it had geometry issues and Samsung took FOREVER to do anything about it.
My parents also had one that gave them issues, though Samsung did act pretty quickly in replacing it.
If you look over on avsforums, most note that there are still geometry issues present on the "slim-design" models. They also had issues with rainbow effects from the color wheel.
That said, I've just never found a Samsung DLP that has impressed me, at any price level.
I do like their LCD's and Plasmas for the most part though. Just my $.02 though.