It might be because of the card I'm using (Samsung Evo Select 512GB) and how much space is being used, or that this is the first release of it. Could be all. In any case, it crashed twice while playing. It also has a major delay on radio stations like VROCK as mentioned in the OP.
EDIT: Given that 3 hasn't crashed for me yet, as well as switching to its stations quickly, I'm ruling out my SD card as the problem. That said, many other things are better than the mobile version. Aiming works correctly, and a firetruck appeared during a rampage that involved molotovs, something that wouldn't happen on mobile. Mobile also has issues with the HUD on Switchroot when switching between handheld and docked. Whatever is used first is what sticks (docked first makes things like HP disappear on portable, portable first puts HP and weapons nearer the center in docked). Not so with this.
So I say it's a great start, and I hope for improvements down the road, since Vice City is my favorite GTA and having it on the Switch is huge. Thanks for this!