I was no longer able to resist the temptation of the Framemeister, and today a package arrived from Japan.
I'm especially impressed with how it handles sources that have non square pixels, such as NES & SNES. The image scaling has the 3 following traits that make it perfect.
1.) Sharp image. None of that bilinear filtering blur.
2.) Pixels are all equal size. No alternating pixel sizes that result in super jagged image.
3.) Proper aspect ratio.
Everything else I've tried (both emulators and scalers) can't do all this. It was always just two out of those three traits. I've never seen NES & SNES look this good on an LCD HDTV, even with emulators. I've seen really high quality Neo Geo and Genesis scaling on emulators, because they have square (or close enough to square) pixels. Of course, they look amazing on the Framemeister too.
edit: In addition to the high quality scaling, the scanlines are another big feature on the Framemeister. Unfortunately, unlike the scaling, the scanlines don't always look great on every TV. The Framemeister outputs its best quality scanlines at 720p, so the quality of your scanlines is very dependent on how well your TV scales a 720p image. Luckily for me, my gaming TV handles the 720p output perfectly, with nice even scanlines. However, on a couple other TVs I tested, the 720p output wasn't scaled as evenly, so the scanlines looked terrible.
In the worst case scenario, you would have to settle for scanlines at 1080p. The Framemeister's scanlines at 1080p don't look as nice because they're too thin. However, it's still better than poorly scaled 720p scanlines.