We landed yesterday at the Douglas PoE (Peace Arch). I was so nervous, I always am when I cross the border. But they were very friendly.
We rolled up, told them we were landing, and after asking us if we had tobacco, guns etc they had us pull over to the side. When we got up to the counter I explained I had my COPR. He asked about my car and if I was importing it. I said later, as I had only just gotten my title from back home in Oregon. He wasn't bothered by this at all and said I could start the process now, but it didn't matter I could wait. I had pre-filled out my B4's and they only glanced at em. My B4's were extremely vague and in huge groups (Clothes and Costume Jewelry; Household, Decorations, and Art; Computer parts and video games; etc...) but they didn't bat an eye. I did write the serial # for my Viola and my DSLR camera. I didn't bother putting my wedding ring on there and he said it was fine.
They had us go sit down and read some stuff about my PR. Then they called us up, said "welcome! You're officially a permanent resident!" and handed me this freaking cute lil flag on a stick hahahaha. He didn't even read my b4 i don't think. Lol. Just stamped it. They didn't care about it at all. He spent the most time explaining the ins and outs of maintaining permanent residency. how to get my SIN #. And sent us on our way !!!