Took some time to install these
So far, I like them. They look soooo much nicer and more upscale than the stick-on models that AVS or even Mazda offers. They may also be more expensive, but they're very high-quality and well-made.
The front window deflectors pop right in the track and fit tightly, without any wobble or looseness. The rears use an adhesive strip to attach to the underside of the top edge, and also pop into place...
One word of caution/warning: I discovered that the rear end (toward the trunk) of the rear deflectors had a large tab that didn't seem to fit entirely within the window frame, and basically shifted the entire deflector toward the B-pillar, so much that it could bend and "pop out" the black plastic trim between the front and rear door. I took a knife and trimmed off about 1/8" of the excess tab on both the rear deflectors, then popped them into place. This improved the fitment greatly, and don't place as much stress on the B-pillar plastic. I'm not sure if the revisions to the door weatherstripping for the '18 models caused the fitment to be shifted, but trimming the excess tab on the trunk end of the deflector seems to have worked.
Weathertech recommends that the deflectors "settle" into place for a minimum of 12 hours after installation, and I fully recommend that suggestion. Immediately after installation, the deflectors interfered with the windows rolling up fully about 75% of the time, so much that it tripped the safety switches and they rolled fully down by themselves. I could only close them fully via "tapping" the switch, without activating the auto-up. However, today, I had no such problem with the windows rolling fully down or up. The deflectors seems to have "molded" themselves into place quite well, especially in the hot sunshine and 90+ degree temps.
We'll see just how well they do throughout the CNY winter also. That, to me, is the ultimate test...