These guys were back to back goodness for the team (JLW left in 1993, MS signed 1993).
Each played the role the team needed at the time - John L as an offensive weapon, Mack as a lead blocker and protection specialist.
Both were fantastic in their roles, I don't think there is a wrong choice - both went to two Pro-Bowls, so they were respected by their peers.
My pic goes to Mack Strong, as I think his contributions to the team were bigger than the on field number differences.
His refusal to go elsewhere when he had other contract offers, and wait on the training camp sidelines until the Seahawks re-signed him, and always playing at high levels during periods of questionable transition for the team, tells me he is 100% Seahawk, and that puts him over the top for me.