Roger at LensRentals.com has done his usual teardown of a brand new Canon DSLR to see how well built the camera is. He found that the weather sealing on the EOS 7D Mark II is the best he's seen in a DSLR.
Roger has this to say about the weathersealing
“So there you have it. This is, by dissection at least, the most thoroughly weather-sealed camera I’ve ever run across. (I would point out that I don’t take apart every camera so please don’t change my wording to say it’s the most weather sealed camera. I don’t know that.) But this isn’t just market-speak weather sealing. It’s a thorough and complete attempt to seal every possible crack and crevice the camera has.”