I had the iNuke 1000 and it wasn't enough to cut through the live mix. Then tried the 3000. It had enough power, but was a bit stale sounding to my ears. Tried the ART-SLA2 and it was the worst imo. On top of the sound quality being much less than the Behringers it also weighed a LOT more and was much larger in size.
I ended up seeing a band played that had the Rocktron Velocity 300 amps running with their AxeFx IIs. I picked one up for about $200 used and it does the trick for my set up (Helix Rack > Velocity 300 > Mesa 4x12). The Resonance and Presence controls work great and can tailor the low and high frequency response perfectly.
Rocktron makes a new model named the Mainline. I contacted their support and they told me the only difference between it and the discontinued Velocity is the Mainline's ability to take line and instrument level signals.