Picked it up last night. Personally I would advise against picking it up on Switch. It frequently seems jittery and sub-30. It can get pretty stressful on the eyes when the speed picks up or you're trying to focus on certain elements on screen. I played for a couple of hours last night and ended up with a crazy migraine which i still hanging around this morning. If it could hit 60fps while docked, even at 720p, it would make a massive difference.
It's a great kart game, I actually really like the customisation options on offer, the team selection and gameplay, I love the addition of different win conditions and missions in Adventure mode. The tracks are great fun too! I would just advise you get this on PC or console and drink in the better visuals and smooth framerate.
The Switch version just isn't coping well, the framerate feels all over and the low res visuals have that Vaseline sheen to them. I also notice that the character selection/customisation screen having lots of issues, with car parts or the chassis flickering in and out of existence just trying to render the models. It just seems like it isn't well optimised for the system, or the system cannot handle the visuals at all.
With MK8 running at 1080p@60 on Switch, it's difficult for me to recommend Sonic over it, even with the lower price. I really hope it gets patched with some optimisation fixes.