Check posted threads in Consumerwatch in regards to the company's you mention,personally I would buy one from Novatech,but its your decision.
On-board and dedicated graphics are built into the proprietary MB's.Its not like a PC where you can up-grade at a later date.
If you will be playing the latest games at some point,then a laptop with a dedicated graphics chip would be a safe bet.
But that said,I have known friends who bought a laptop designed for gaming and still found issues with the games settings,resolution,in game graphics settings and AA.
Personally I don't like playing games on a laptop,but like I said its your decision.
Hope this helps?.