I think I saw a comment on TGP about slow patch changing. It was cured by forcing the Helix to rebuild presets at power-up. That's holding switches 10 and 11 on the floor/LT.
I've been using the Helix on bass for quite sometime now. It replaced my entire pedal board. The best feature is being able to run dual channels for you bass. So you have the modeled sound with the plain sound. It's pretty awesome!