OK how about a third option. I was thinking about doing all the same stuff, but I don't like older classics on 25" monitors. Obviously vertical games would look great, but horizontal games would run the full 25". Anyone know a setting that allows you to run a horizontal game scaled down to about 19" size? I know this would be a HUGE stretch, but it would be cool to have a 25" H monitor running 25" for newer jamma horizontal games like NBA Jam, but then use a horizontal 19" area for the classic horizontals like Crazy Climber. I think the old classics on a 25" look like crap. Hide this behind a smoked plex bezel and you could hide the borders on the monitor pretty cleanly.
I guess the other option would be to use the MAME bezel feature for those games. That would be interesting too.
Anyone ever think to do this?