Since SteamOS 3.5 finally released into stable, I’ve been looking forward to try out PS3 emulation on the Steam Deck, especially the Uncharted series & MGS4.
Long story short, performance was rather subpar, with frequent FPS drops.
Looking around, I came across this post on Reddit:
https://www.reddit.com/r/SteamDeck/comments/16ydaoz/mgs4_on_rpcs3_with_full_visual_effects_on_the/
After applying the tweaks referenced there, I really did saw a boost of a few more additional frames, but the real improvement is that the frametimes become more even, resulting in noticeably less stuttering.
With a 50 % resolution render scale, Uncharted 1 can be considered playable on the Steam Deck, IMHO.
Hope these tweaks help you guys out, too!
Switch emulation has been pretty good in my experience. The weird differences in performance have been when I run games in desktop mode compared to SteamOS. Some work better in the former and others the latter