When carrying out IMC training, we always make it plain to ATC when we change to VFR, usually for recovery to base. We always benefit from a positive handover with squawk given in advance of frequency change when moving from one unit to another under IFR, so the IFR conspicuity code has never been an issue. Our transponder is programmed for 7000 when hitting the 'VFR' button. I've yet to encounter a situation when under IFR, that I've been asked to squawk conspicuity and would hope not to.
TOO