Coleman is good. He is probably top 3 RB in the league along with Zabaleta and Sagna.
What he is not though, is worth anywhere north of £10m and you just know that's what Everton will be asking. You just dont pay these sums for RB/LBs. If Utd want to go and splash £25m or more on Shaw, they can go ahead.
I would gladly settle for Aurier for £5-10m if it meant we can spend rest of the money we would pay for Coleman on a striker or midfielder instead.