I fired up Neural Dsp's Gojira plugin and it just kicked butt!
Im still considering going into a guitar store to test another kemper.
Imagine i test out another unit and it sounds incredible! I would literally cry lol.
I took Neural's SLO 100 plugin for a test drive. Jeepers, it sounds so good. I'm going to buy it for my laptop when I travel and can't take my Kemper.
The GC thing is a good idea. If your Kemper does have an issue a side by side comparison will bear that out it. If they both sound the same with the same profiles (very important) then it's unlikely they both have the same issue. Then it could be the profiles. Or maybe your ears just don't jive with the Kemper. It happens.
Let's assume your Kemper has an issue. That being the case, how do you plan to get someone to buy it as is? But then again I traded for my Kemper without trying it out or ever even having heard one in person so there ya go. Good luck in your sonic journey wherever it takes you.