Nobby,
I too own a tv-tuner card Matrox G400 Marvel and you are right, the tv images are great !
BUT : The (composite)video outputs of gameboys and keyboards cannot compete with those TV-images because graphic cards can interpollate and eliminate the refresh flickering.
The resolution of keyboard LCD-displays is about 250x150 (or a little higher) pixels and the video-output is based on this resolution and will not be more accurate. (PC's have 1280x1024 or 1024x768)
As DonM wrote : "For lyrics presentation the video-out is OK" (Karaoke)
For full-screen use I expect unsharpness.
Roel
[This message has been edited by Roel (edited 03-31-2002).]