Ertz or Lockett?

12-team, STANDARD league. We do NOT require a TE in our league. We simply have three “WR/TE” slots. Who would you rather have as your WR/TE3: Ertz or Lockett?

I currently have:

WR/TE1: Hopkins
WR/TE2: Edelman
WR/TE3: Z. Ertz

I am considering trading Ertz for Lockett. What do you all think? I think Ertz is extremely safe and a good anchor as my WR/TE3, but Lockett could be a league-winner at WR3.