I'm trying to remember...as it was when I first got my Helix. I tried the Helix thru my QSC K10 and it was alright. But it wasn't what I wanted. However, my main use for the Helix is for effects and Variax control. For me, the amps and cabs are secondary. I was using amps and cabs when running into the K10, of course.
If I recall correctly, I then ran the Helix into my Fender DRRI, and things were infinitely better. I gigged with that rig for quite some time. I didn't want to keep lugging around the DRRI, tho. About 50 lbs in its case, plus I wanted to get away from the tube world...the maintenance/fragility and weight aspects of that world, anyway. I have been all about streamlining my rig. Cos at 3AM, the less stuff you have to unload, the better.
Ultimately, I wound up running my Helix thru a Quilter MicroPro Mach 2. Oh my stars. Sounds amazing and weighs 18lbs or so. 8" speaker. How can this be? :o
I'm sure running direct for recording and such will be fine. Haven't tried that. All my tracks get reamped anyway. For live, and for me, tho, it's the Helix and the Quilter. Fantastic.
Cheers!