Things I will not buy without trying them on: cycling helmets, and cycling shoes.
When I cracked my Smith, I went to the LBS and tried on every single helmet they had in my size. Bought the one that fit the best.
On my odd noggin, the fit of all of the POC helmets is... undesirable. Kask was the winner. The new Oakleys are nice. Came out too late, as I had already bought the Kask.
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