my snes mini looks quite good through the framemeister and using retroarch. I don't own a 4k tv though. it, the framemeister, can upscale up to 1080p, which may or may not be good enough. it's very expensive for two reasons: Japan only and it's been discontinued. I managed to get one from solaris of Japan, but they've run out of them since that time. your only option really is amazon or ebay where it'll most likely be used. last time I looked, they were going for over $800. on solaris, they were $333 iirc so still expensive, but once they ran out, the price skyrocketed. I think my framemeister may be more expensive than the tv it's plugged into, but I have 10 devices going to it to my 1 hdmi on the tv. the framemeister only has 2 hdmi ports, so I had to use hdmi splitters as well.
anyway, there's also the ossc, but it's stingy when it comes to tvs. some work; others don't. you'd just have to test. those go for somewhere around $200 I think. I think they might still make them, and the software is open-sourced, unlike the framemeister's, which no longer sees updates. I've only updated once as the one from solaris was on the previous update out of the box.
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slight glare from outside, but that's at least what the framemeister and retroarch look like on the psx classic.
