Interesting and informative clips, Elros, thanks. Right off the bat, I like the GR-20 harmonica and trombone sounds better than my GR-33. I do notice the latency most on your harmonica sample, though in a way it's cool because it sounds like someone accompanying you rather than a perfect note for not match. Also, as you mentioned, latency can vary depending on the patch (pianos have the worst latency on my GR-33 with my guitar). But when you say that latency is worst on lower notes, what range are you noticing it? (Open E and below, or A and below, for example?). You mention you're primarily a fingerstyle player, and so am I. I'm remembering now in discussions that when players were comparing the Roland units to the Axons that the one caveat with Axon was that players thought that the Roland units responded better to fingerstyle guitar playing (I'm assuming because you can fine tune the play settings (i.e. normal, fingerstyle, tapping, etc). As I'm not familiar with the GR-20 yet, can you fine tune playability settings like the GR-33? Also, can you assign different patches to each string like the GR-33 (or combine 2 patches to a string?). The one thing I do like about the Axon units is the ability to split the fretboard up.
I'm glad the subject has been revisited. 
