The BOSS GT-6/8/10/100/1000 units had gapless switching down to a science even in the early 2000s. I think this really had to do with the fact that they are pedal company first. Every change of a preset (or their take on "scenes") is as instantaneous as stomping a BOSS pedal, no matter how many changes happen internally. The trade off was always quality of amp and drive pedal modelling. My view was always "Fractal" for recording, "BOSS" for the gig, since a lot of my band's songs need instant switching from clean to high gain. Also, the BOSS GT-1000 limits you to 2 preamp blocks, which is generally sufficient. If this change can be ported to the FM3 or FM9 that would be 4 and 8 amp channels respectively.