DVD transport mechanisms on high-end players?

Does anyone know the DVD transport mechanisms used in the various high-end DVD players on the market currently (Krell, Lexicon, Linn, Esoteric, Bel Canto, etc...)? I am beginning a quest for a new player (still uncertain on functionality vs. price) and feel the source (internal or external OEM) of the transport mechanism is an important, yet rarely advertised piece of information. I can do my own leg work on this, but I need some focus (Google searches are too broad).