This is Permatex we're talking about here. It's not like they're new to the sealant game and the product is specifically made for this purpose. Have a little faith fella'!That sealer, it's easily removable after a couple of thousands of miles? It won't be hardened and hard to remove?
And that's the same experience I had on my Miata. 110k miles of reuse and it never leaked, but the washer itself was about twice as thick as the CX-5 washer. Keep an eye on your newly installed washer. I thought mine was sealing properly after my last oil change, but after 2500 miles I checked it and it was leaking again! Next time I will use the Permatex plug sealer for sure.