Just to be clear, Jake Ordizzi was also part of the trade. He was a top 100 MLB prospect in 2010, 2011, and 2012, so he's not exactly chopped liver... definitely not a guy I'd want to trade 1-for-1 with Wade Davis.
If Kansas City was willing to do Meyers + Ordizzi for Shields + Davis, would it be unreasonable to see them trade Meyers for Lester straight up?