Nice one, Shep. It's a testament to your ability in engaging the realm of the organic (the playing) with the high-tech tools & toys available to get such a good sound.
Not taking into account the bundled software that comes with various hardware interfaces, the free vst's I have found so far range between bloody awful to truly shocking. The Le Pou plugin called LE456 is the best I have found so far, and still it's not so hot. Too much overdrive & distortion, even when the controls are down low. And I say that as someone who LOVES a lot of distortion in my tone
The vst's however just sound raspy and fuzzy. If anyone remembers the old Rat Pedal, it's like that !
As much as I think it's a so-so amp for FX, I think I'll stick to my Behringer cabinet and use the Reaper effects to colour that signal.
Or, I could always record guitar through my line out and add Reaper FX, and on a second track simultaneously record the amplifier with a microphone, then belnd the two for a unique sound.