I used to gig with a Bass Pod Pro XT and that was great. The Ampeg models were excellent, but lots of the others, like the old Hiwatt guitar heads were really useful too
The most fun was using things that aren't really for bass anymore- like the Fender Bassman combo. You could use a combo now, but the power output and speaker fart-out would be a problem with a loud band. But with the Pod XT I could set the tone how I wanted and then let the dirty great Yamaha power amp I had do the heavy lifting.
The mixing in some direct clean was the icing on the cake.
The Helix will allow a 4 way parallel signal, so that could be mixing 4 amps together with separate EQ blocks, and again it won't matter whether the models are for bass or guitar, it will only matter whether it sounds good to the player.
It's the sort of kit that makes rhythm guitarists redundant!!