So...the Shield Tablet K1..How is it?

So I’m thinking about picking up a Shield Tablet, with RA being one of the reasons. How well do some of the higher-end cores like Mednafen PSX & BSNES Balanced? Is there any stuttering or crackling audio with cores that run outside 60hz (Wonderswan @ 75hz and Virtual Boy @ 50hz) How’s input latency?