Now that I've had a chance to have a good mess around with the Plex, a few thoughts:
Due to each knob having a secondary function when pressed down, it takes quite a lot of getting used to, as do the very bright white LEDs
However, for tone shaping, there are multiple ways to get the tone you're after, plus the 'voice' option, which gives you amp sims of Gallien-Krueger’s 800RB, Fusion 550, MB800, and MB150 heads.
It should be no problem to tweak the 'darker' tones of a short scale.
The compressor is very good & quite flexible - makes a difference!
I don't normally use overdrive, but I had a play and you get 5 settings from mild drive to buzzsaw metal! Plus of course, the usual level / tone controls. I like the mild OD setting on this.
It's not cheap, but I'd recommend it - however, I have also used the Eden WTDI for a couple of years in home & open mic situations, and you might achieve something similar with this, at a lower cost. It's also very good.
In summary: Pretty comprehensive tone shaping.