Grills on normally, but I still take them off on the rare occasion I can spend some serious listening time. I don't think the sound is really any different, but having the cones visible seems to add something to the experience.

I realize it should be the other way -- conceal the speakers and support the illusion of being wherever the music was recorded, but I don't have enough imagination for that anyways

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8