We've used ours on the back side of ribbons for guitar cabs, and to cut room ambience from room mics (um, that didn't work out so well... or it worked REALLY well, I should say, but it defeated the purpose of the room mic, I guess).
Just did a project where we tracked all the lead vocals in the control rooom, live, with speakers on (no phones). Korby mic, right in the middle of the room, tons of rock n roll vibe on the takes, and the bleed was really manageable. It really allowed the singer to feel less like he was in a studio, more like he was performing. I know cutting vocals in the control room isn't ground breaking, but the Reflexion Filter worked surprisiingly well to help cut the band from the vocal track.
