Do the Aura preamp pedals care what guitar the piezo is in? I mean, do the dreadnaught presets work better with a dreadnaught guitar? Do the others work just as well if I use a dreadnaught on every preset? (and so on...)
I use my parlor guitar with the dreadnought pedal and it works well. Does it work better with an actual dreadnought guitar? Maybe, but there are so many settings and ways to play with the pedal I am usually able to find the sound I am looking for.
Check for updates. I have one of the older, guitar-specific ones. Turns out there's a mini USB jack behind the peel-off backplate and you can download new profiles from Fishman. I re-did all mine to work with my two main acoustics that have piezo pickups.
I find it matters. If I use a dreadnaught image with a smaller bodied acoustic it comes off as boxy with quite a bit of mids present. Go ahead and experiment but I think you will find that the images work best with guitars that they were intended to be used with.