Line 6 Have reportedly been working on this next generation of DSP modelling for over four years. The all new Helix uses a new HX modelling technology which utilizes dual DSP chips to get the most authentic tones - so they say. Another new feature is the ability to load 3rd party impulse responses - not clear if this is just for ambience or more in the Kemper model - where you can 'sample' other rigs.
It sure looks nice, with a new 6.2" main colour LCD display, scribble strips for each (capacitive touch) foot switch and plenty of IO. Line 6 bill it as a tour-grade multi-effect pedal. You can also edit the patches more easily with your foot - by using the rocker expression pedal for data entry - smart move.
Available shortly, Sweetwater have it listed at $1499