The two teams are having good campaigns so far, as they are both among the top 8. However, Arsenal is in a much better situation, as they are in 4th place and fighting for 2nd place. They have the second best attack and a good defense. West Brom has modest stats. It is clear that there is a huge difference between these teams, as Arsenal has more high quality players. So, due to their great attack and being at home, it is a good option to back a match with more goals than usual.
My tip is : Arsenal to win and Over 2,5 goals FT @1.96