I'm using mine that way until my MFC ships (Monday). It's okay. It's limited compared to the MFC obviously, but it does work. Thankfully a friend knew how to set it up, so that saved me about a half day or so.
The tuner works fine, but you can't see it on the HD's display. But if you program the tuner button for the Axe's tuner, you can't use the HD's tuner. And it's instant, BTW - just touch it, no holding it down for a couple of seconds. Since I find I hit that HD's tuner switch with my size 13s (used to mute myself now and then), I set the Axe tuner to not mute. You can pull the treadle back instead, works fine.