Everyone's expectations are different.

I would recommend the large which would give an "appropriate" fit. Ie. Form fit, but not restrictive.
However, if you (or others) are seeking an extremely tight - Speed-suitesque - fit I could understand why they went medium. In that situation the garment will probably be stretched to it's capacity. This situation will probably impact both your mobility and the lifespan of the garment.

I also confirmed this with our wear-test analyst, who sits next to me.

I wear a medium and I'm 5'11" / 163lbs.

Let me know if you have additional questions.

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The above poster has eschewed traditional employment and is currently undertaking the ill-conceived task of launching his own hardgoods company. Statements are not made on behalf of nor reflective of anything in any manner... unless they're good, then they count.
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