Are there any VGA switchboxes that actually do a good job of switching displays between your GFX card and ScanDoubler, without any loss of picture quality? I suppose that those expensive ones are the ones to look for.
I have a cheapish ($10-$20 range) switchbox, and I can clearly notice that the display coming out of Voodoo 3 is not as good as it would be if it were directly hooked up to the monitor. I don't notice any big difference with the ScanDoubler display, but the high res RTG Voodoo 3 output looks terrible (kind of blury). The extension cables coming out of the GFX card and ScanDoubler to the VGA switchbox are both of good quality (StarTech make), so I doubt that this is the problem.