Interesting, I'm planning my next shifter, I don't have one, it will be the first!
So which is your favorite shifter, and why? do u think digital vs analog makes sense for a shifter comparison, or own both kind of approach do u think ?
-- fzzz
My 2 cents:
Own both is a very valid approach IMO if you have the $ and the space in your rack. I currently own the following frequency shifters myself:
Sketchy Labs Freak Shift (analog)
DACS Freque II (analog rackmount)
Mutable Warps (digital)
Happy Nerding FX Aid (digital)
I've also owned the SynthTech Deflector Shield in the past. My experience so far is that no two sound alike, but of course the ones that can accept external carrier signals have the potential for more variety of sounds. But IMO having the ability to output the up and down-shifted signal so you can mix/invert/otherwise process them before feeding them back into the module might be even more important in that regard. Note also that some shifters are limited in how much they can shift, which could be an issue if, for example, you decide you want to do octave shifts with higher-pitched signals.
Of the shifters I've used I'd say that generally speaking I prefer the sound of the analog ones, which in my case also offer a lot more control. But of course the digital shifters I own do a lot more than just frequency shifting. Still I'm glad they have that capability, sometimes your dedicated shifter is occupied and you want to shift something else, well then Warps or FX Aid can come to the rescue. So that's how I look at it.