This is the sixth time I've tried to reply. Kids keep pressing buttons while I type. Anyway, I like the rulers. My first time to use them, and as long as I cut carefully, I am getting correct sizes with no sliver trimming. I like, for this stage of life, not having to do math. Obviously, I am frequently distracted and using a regularly sized strip is a plus. I like having to only cut once and having half the dog ears already trimmed. So anyway, if your strips are already cut, and you have the rulers give them a try. If you are uncomfortable with them or can't get ahold of them then go with what you know. I used 8 strips of background and 8 of color for the geese.
Did you cut your background bricks yet? They will use up some of those strips you already have. I think it will be 5 or 6 at WOF.