I just self cleared 2 guns coming in to Canada from the US via UPS because I didn't want to pay their ridiculous brokerage charges.
It comes down to the CBSA officer. The guy I had basically just did a google search and looked at the product page and some youtube videos of reviews and testing of FPS then let them through. Some will actually test. Some will go strictly by the product page. It's really up to each individual CBSA officer. If you get one that doesn't want to test it and goes strictly by the product page you're probably hooped since TM guns from Japan would not meet our 366 minimum.