Given that the image is Pal or NTSC not HD then you could probably get the same image quality using a cheap P&S without putting mileage and heat concerns on your Kx.
From my experiments the difference between the view from my Sony 6Mp P&S and my K200D (when used into a TV or the video capture to the computer) is minimal.
Like your idea of a low power large view microscope use !
Must go and try it for hand engraving on metal.
Hmm, might be good for a demo screen when I am teaching Jewellery classes. Right, off to try that too !
Thanks for your inspirations...