Great question. I think it's good to know who is using it to see if you think it'll fit stylistically and functionally. I don't see the question as a slight to the product, but as a way of saying "who do I know that's using it, and how can I use it like they might?"
We were looking at a lot of options for our electric guitars at the church I work at. We set up one amp in a sound enclosure with a Radial SGI Interface, but after looking up some of the amp modelers and profilers, we started looking at the Helix as an option. Brian Wahl from worshiptutorials.com did some great demos on YouTube and uses it along with another rig that has a standard amp and pedal setup.
Then I started digging more, and I found out Lincoln Brewster uses one in his live setup. He always has amazing tone and I thought that was a good vote of confidence moving forward. The more digging I did I found some other artists from bands I love use the Helix. One of the guitarists from Thursday uses it, as does Minus the Bear and the newer Smashing Pumpkins guitarist (not Iha, but that's ok).
If you're ever interested, equipboard.com is a great resource to find out who is playing with what gear. They have pretty much everything listed, and you can search by gear or artist. Hope this helps!
http://equipboard.com/items/line-6-helix-guitar-multi-effects-floor-processor