My method of choosing a wood arrow is simple. I pick out several of the longer ones from the lost arrow bucket at the club' s range, find out which one shoots good for me, take it home and put it on my homemade spine tester. I usually have to add 5 pounds or so because most of the arrows in the bucket are an inch too short for me.

By the way, I do put the borrowed arrow back in the bucket the next day.