Don’t own the JP8 but the JX & JU I have.
Yeah the sysex & mod wheel stuff is gimped but they are so easy to tweak on the fly & sound sweet doing it.
Found the Octatrack goes best with them - resampling the tweaks for temporary or permanent prosperity.
Running them into anything that can sample/loop allows repeatable manipulation.
The MD UW would be an entirely useable option for ‘temporary’ capture.
Shitty workaround for parameter locking - building some kind of sysex-cc translator in raspberry pi/Midi Pal/Midi-ox/Midi Designer