We share a couple of things: we both love high gain Metal tones & I used Line 6 stuff from about 2001-2014. After going to Randall solid states, I'm now back in the digital world with the Kemper. Only had it for just shy of a month, but here are a few bullet points from the experience so far...
- I recently upgraded from BOSE computer speakers to Presonis studio monitors. Huge improvement.
- In-ear monitors sound KILLER with the Kemper. I can tweak tones at 3am, not bothering a soul, and the next day though the monitors, the tones translate very well.
- Cabinets! Go searching for cabinets! They make or break tones! Most of them are truly horriffic, but I've found three or four that sound incredible.
- All of the high gain stuff on the Rig Exchange is absolutely dripping with gain. Most have the gain dimed. Dumb! Back it down to 6 or 7.
- Overdrive pedals are your friend. Treble boosts work great, too.
- Edit presets that are for certain circumstances: I make ones for in-ears (lotsa "Space" knob), ones for the monitors ("Stereo Widener" is GOD), and ones for rehearsing/live...although I've yet to jam with anyone so far. But you have to be prepared.
- Michael Britt's Profiles are amazing...except for the high gain stuff. Go to the Rig Exchange and try lots out. The Diezel VH4 is my Holy Grail Rhythm Tone. OMFG. Don't go down the rabbit hole of buying Profiles. There are so, so many great, free Profiles to choose from!
Hope this helps to some degree.