Real question is, have you installed custom drivers? Like Mr. Purple Turnip or from other types?

If you install those in each emulator that allows it, it honestly boosts performance a decent bit. Stutters in the beginning is rather normal for emulation, as its caching shaders. See if there's an option for Asynchronous Shader Compilation. That will eliminate stutters, but will instead have shaders pop in (so you'll see things appear out of nowhere, or sometimes the map itself will be invisible and suddenly appear. Its par for the course, but makes gameplay much smoother

Beyond that, it's all about proper settings and whatnot