It's been done, and real LD fans buy all kinds of line doublers and scalers to have the best image possible.

I think they'd look okay depending on player/setup but of course you're going to have all the format's limitations magnified. If you've got a player, see what a disc looks like on your TV. That will tell you most of all. Try with composite and s-video, though composite will give a better image on modern displays.

Also keep in mind each player has a different quality, with some being better in image than others.

I went the route of getting a late model CRT set via craigslist, and actually got mine for free.