I connect to seattle. Which ever has lowest ping at the time.
Just choose server hit connect then launch archerage.
I notice a huge improvement using it, still not perfect, get out of range when players are standing in my face maybe 40% of the time compared to 80% without using it.
EDIT: I hear if you have average ping without battleping you wont really notice a change. I'm in New Zealand and was getting 240-400ms without