I've often read this, but I've never thought that the SLO was the Recto tone. More of a Marshall flavor. Recto tone is the most Brutal metal tone of all time, SLO seems smooth in comparison.
For a fraction of the the Synergy stuff, I have the tone I need, C+++, and another + if needed with my Boogie Quad preamp and various seriously incredible matching power amps. The other half my equation is a Marshall stack. When I run them together in conjunction with the Mimiq, it is not too bad.
There is something about new amps the give my ears fatigue after a few hours.