We were stopped by an marine RCMP officer in a RIB a couple of summers ago - he was mainly doing a PFD check... This was probably the only time in over 20 yrs we were out of compliance - we had some unexpected guests for a daysail who had not brought their own PFDs as we requested, and so we were a couple short. I rather sheepishly explained the situation and was fortunately let off with a warning.
We immediately purchased a couple of guest PFDs to have on board at all times. I have no problem with these types of checks - it seems to me that only those with something to hide would have a problem.
And in the past 28 years on this coast that was the first and only time we'd been checked by anyone (police or coasties) while sailing.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)