Advice on buying used Rokinon 14mm 2.8 lens

[kulansha2]

Was looking to buy a Rokinon 14mm 2.8 lens for astrophotography/landscape photography. My widest lens right now is 50mm.

Im looking to buy a used example off of MPB or KEH. I’ve heard that some copies will have issues, how noticeable would it be and what should I look for? And is one site better than the other at honoring returns?

[shadowsports]

 Greetings,

I own this lens. I used it two or three times with my 6D mkII and retired it when I upgraded to mirrorless.  Zero issues. It was sharp and worked really well.  

Both mpb and keh have good return policies.  The front element is convex so it protrudes.  I always used it with the petal lens hood.  

Things to look for... smooth focus throughout the range.  Positive clicks on the aperture ring.  I'd mount it on a camera and use the depth of field preview button to ensure it stops down correctly.  I'd also make sure that the mount for the lens hood and for the camera body are in good condition.