I have. And the responses are a mixed bag with the fine (or better than fine) side being the response on average.

I've had my bad experiences with CBSA but they are limited. If you know how to handle them, then you can handle the situation and you will have a fine experience.

In fact, the other day coming back into Canada, my experience was:

Agent: "Where are you coming from?"
Me: "XXX"
Agent: "You were there for work?"
Me: "Yes."
Agent: "Who do you work for?"
Me: "XXX"
Agent: "You were on a farm?"
Me: "Yes, to visit a friend."
Agent: "Did you go on the farm?"
Me: "No."

And then me: "You're not wearing your vest today?"
[stamp]
Agent: "Yeah, I'm breaking the rules today. Welcome home"

That was pleasant enough.