Before I bought this monitor I was trying to find a way to kind of simulate what 240p games would look like on a Sony BVM.
I used my CRT PC monitor, took a Neo Geo emulator (Kawaks), activated a scanline filter and set it up to output at 640x480 in fullscreen.
I took a picture of this:

Would a BVM look like this? While it doesn't look bad, I don't really like it. When playing with emulators I never used scanline filters. At the beginning I used 2xSAI or interpolation. Later I preferred to use a simple 2x nearest neighbor filter and I played in windowed mode instead of fullscreen.
With a scanline filter the image looks too dark and dull to me.

Some years ago I saw a Metal Slug 3 arcade machine at a japanese movie festival. I don't know whether it was real hardware or emulated, but it looked very much like what emulators with scanline filters look like. The machine was set to free play. I didn't bother to play because of the dull looks.

Now that I have a BVM, I can compare. So here is what it looks like on the BVM D32:

That is much brighter and vivid. Definitely more to my liking.

As I have shown a couple pages ago the Samtron monitor and the BVM have very similar looks. So simulating it this way was not a bad idea. But why is the BVM image so much brighter then?
The BVM has a setting which the Samtron monitor does not have: Subcontrast.
This setting is not available at 1080i. It is only available for resolutions lower than 1080i. You basically use it to make lower resolutions look as bright and full as 1080i.

A 640x480 image on the Samtron monitor looks already quite a bit darker than a 1024x768 image. The monitor has less lines to draw and the lines are not as close together. If you add a scanline filter on top of that it becomes even darker. And it does not have a setting like the BVM to compensate for that.

The first picture does not really show it, but with a scanline filter, the scanlines and blanklines indeed have the same strength. On the BVM they don't. The brighter the colors it has to display the thinner the blank lines will look. Compare the bullet or the Metal Slug logo.

If you want, you can get this dull look on the BVM too. Just lower the subcontrast and/or the regular contrast.

I don't own a Neo Geo. That photo from the BVM also shows an emulated Metal Slug 3. Emulated with GroovyMame and output in 240p, the graphic card is connected to the extron rgb interface, the interface with the BVM.
Noteworthy here is that this kind of setup requires different settings than a real console connected through a scart adapter. The subcontrast setting goes from 0 to 200. For consoles I use 200, the maximum. For the GroovyMame setup I have to lower the subcontrast significantly to 90 or something. At the moment I don't use GroovyMame much, but if I do I don't want to adjust the subcontrast setting every time. A solution for this is to play consoles in 480i normal mode and GroovyMame in 480i underscan mode. You can set up different subcontrast values for each mode.
Below a picture of the game with subcontrast at 200. It's really a bit too much, look at the Metal Slug logo. It's even worse if you see it in person.