Speculum Speculorum
Power User
Hello Spec, my current rig is the XL+ Plus and yes, FRFR, using the QSC K-10 floor wedge.
Right. So here's the deal. Even with plenty of volume a FRFR system is not going to behave exactly like a power amp and real guitar cab.
The QSC is amplifying an impulse, which is great for fitting into a mix, but it won't behave identically to an amp and cab in the room, which is partly what creates that guitar/speaker interaction that gives you the controlled feedback.
I know people say they get sufficient results from FRFR when it comes to getting feedback, but due to how frfr works it won't give you the exact replication of that feedback interaction you'll get from a real cab.