Ah well, I wasn't exactly in my right mind when evaluating the effects on the Studio 40.
After absolutely no one agreed with me about the effects with an expression pedal I assumed either, A: No one else is using an expression pedal with their effects, or B: It's not the amp, it's ME!
It turns out the effects aren't all jacked up like I originally thought, they just need to be adjusted. EVERY detail needs to be adjusted.
I finally got the pitch shifter to respond in a pleasing manner by adjusting everything, but mostly the toe/heel settings.
The default setting is really low for the Up position & really high for the Down position, which is why it sounded like a robot maneuver when being manipulated.
It even works well with guitar now that I have it adjusted right. No more idle pining for a double-locking vibrato guitar!
As far as "studio-quality" effects go, I'll hold off on that judgement until the day that I can get a closer approximation of the Wah on Black Sabbath's N.I.B.: