I recently left my V2 integrated on for 72 hours straight, driving Thiel 1.6's for breakin (3 ohm min), and found that there was a little residual RFI interference on cheap FM tuners by the end of that period. Perhaps the long time and heat build-up changes component spec just a bit. My high quality Denon FM tuner is not affected at all but $30 clock radio had a hint more static at that point, which disappeared when I turned the integrated off.
However when I first turn the V2 unit on, there is no static even on the cheap FM radios (unlike with the V1, where the cheap FM radios were unlistenable immediately upon turn-on of the NuForce).
This is my long way of saying that I've decided to NOT leave my NuForce integrated turned on 24/7. Usually with solid state, I do leave it on 24/7 unless it has a high bias to class A.
Art