Hi.
In no particular order....(brain dump)
Sounds are obviously identical.
Addition of headphone output and master volume is Awesome!
loving the colour screen, all the info in one place! and color represents block type so its easier to see at a glance what the blocks are doing. on the HXFX there's a lot of info, but its all spread around, and in B+W.
moving blocks around the chain is harder, and unnecessarily so as there's plenty of knobs. You have to use Cut/paste
the knobs seem to respond better.
i love that it shows the midi PC on the preset selection screen. this makes it so easy if your using a midi controller.
love the form factor Its TINY!!!!
i wish they had put the screen on the RHS as i tend to play notes with my right hand and change parameters with the left. doing this mostly covers the screen with my hand. still, better than the HXFX
i will miss ability to turn off more than 3 pedals on the HXFX
addition of HPF and LPF in the global is awesome!!! HXFX doesn't have this
copying blocks to another patch is easier on the stomp
ill come and edit this post if i think of any more differences