I have a Mesa dual rec 3 channel, this amp is really good and many sounds can be found, if the helix can do 80% of the Mesa I will be happy.
Also I had a mark v, I don't see how the helix could get all the sounds that amp is capable of.
But in the past I tried line 6, boss gt's, zoom and others on Mesa amps, and Mesa amps don't like them, tried the Roland cube with boss-gt 10 and 100, was ok, I have tried these pedals on powered monitors and again just ok and left me wanting.
I'm going somewhere with this just hold on.........I have just got an ENGL power tube amp (older one) and this is amazing, I have tried it on many pedals and it makes them all sound great. Even cheap digitech pedals from years ago sound good on this ENGL.
I just took back a boss gt 100 and put the money on a helix. For some reason the boss gt 100 took the tube feel away from the engl but it still sounded really good.
So I'm waiting on the Helix to get in so I can hook it up to the Engl tube power amp......this may be a spectacular combination.
I haven't owned a axe fx but the ones I got to hear were pretty good, the boss gt 100 played into the engl comes close to what I got to hear from the axe fx, so I can't wait to see what the helix can do.