I like 16:10, since it's the best of two worlds.
Films. 16:9 films don't completely fit a 16:10 screen, but that little free space can still be used for control elements of a player or Windows task bar.
Media Player 9, afaik, has the control panels in full screen mode were the black bars are.
Also, 4:3 films can occupy more space than they can on a 16:9 monitor.
Sure, a 4:3 monitor is superior here - but most 4:3 models top out at 20" or 21".
A common 16:10 monitor of 24" or 27" and up comes close to that 20" 4:3 experience .
PDFs. Scans of books, magazines and comics can be viewed good on a 16:10 monitor (two pages).
A 4:3 monitor is too small in width here. An 16:9 monitor misses some height.
Emulators. 16:10 monitors can display classic 4:3 contents better than 16:9.
You get a few centimeters extra with a 16:10 monitor of same size of a 16:9 model.
But that's just my opinion. I'm using a 4:3, 21" monitor for VGA and SVGA resolution at 640x480 / 800x600 pels, respectively.
The 286 PC I have runs Windows at 800x600, which displays nicely on a 1600x1200 panel.
5:4 is also interesting, but worse than 4:3 or 16:10, perhaps.
Because, the visual distortion of 4:3 material through stretching makes an oval out of a circle.
It's like running 320x200 games at 16:9, imho.
5:4 is what old game consoles (SNES) used internally due to the resolution limits imposed by LD monitors (max 240/288 odd or even lines),
but what never was meant to be displayed unaltered.
Edit: That simultaneously means that 5:4 monitors are nice for pixel artists as a secondary monitor.
They can see their 5:4 art raw, without distortion. That makes editing/drawing more pleasing.
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In what to one race is no time at all, another race can rise and fall..." - The Minstrel
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