I downloaded and double checked Jet Set Radio and yes it is framerate locked, no it is not resolution locked.
It also works with GeDoSaTo, which is nice.
I think I remember being pretty bitter on it because I was really hoping for 60fps, and when you're in the menus there's a SMALL glimmer where transitioning from main menu to career menu that the game runs at 60fps. I actualled messed around with Cheat engine and you can make the game run a bit faster with the speedhack and it gives a nicer framerate. Of course, the game is running at a slightly faster speed however, which could be bad (I actually like the faster pace!)
Also, pairing it with GeDoSaTo's post processing options, you can pull off more vibrant/really cool stuff with the looks.
Vibrant
More edge lines
Sin City shader
Alright I was wrong. Port redeemed. I'm a dingus.