I have the RTX 2060 Super and it works pretty well in SL using both Firestorm and the official viewer, though I did have to do a little tweaking in preferences to get it looking the way I wanted. One thing I have noticed is that some apps (not SL, Slack, Amazon games) don't seem to like the graphics acceleration on that card along with Windows 10. The apps look pixelated sometimes. Some you can turn that off, others you can't.
Otherwise I'm in love with card and so love the liquid cool vs. the loud fan. Mine is in an Alienware Aurora R10 with an AMD Ryzen 7 3700X