Chark is legit but battling through injury.
Westbrook is legit but battling through injury and being utilized poorly.
(he also is going through a little slump with his hands - happens to most receivers at times)
Conley and Cole are worthy role players  that will linger around 3/4/5 on the depth chart.
All of them are getting adequate separation at the top of their routes fairly consistently with Chark and Westbrook doing so impressively at times.

The primary issue is lack of protection and throws being made early, late, and/or under duress.

I'd draft a receiver, but I'd wait till the 4th or 5th round depending on who falls in a deep class. 
Too many other greater needs like NT, LT, MLB, TE, OG.

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