I have been running in stereo, to a stereo PA, since 1991. Back then, it was my ADA rig. Since we play in bars that are not huge, the stereo is noticeable to the audience, since I can tell it is stereo with the break music. With the Fractal, I used to run my Martrix CFR12’s in front of me in stereo, but we switched to in-ear monitors a few years ago (Deaf bassist blasting me off of the stage!)
we run outdoors in stereo as well, with more PA speakers, and it is still noticeable. Just my guitar is in stereo. We have bass, drums, and vocals center. Maybe panning the Tom’s on the drum kit a bit. It was great fun to take out my in-ear monitors during soundchecks, and go out front outside, and have someone switching my scenes on my pedal to audition the stereo effects on the big PA!