Pinking shears are not used in piecing quilts. Seams are sewn at 1/4 inch, the zig/zag when using pinking shears cuts into your seam allowance. Less fabric in the seam allowance will make the seams weak and will pull out after some use.
Rotory cutters are the best thing ever invented for quilters.
When using them with quilting rulers we can cut precise pieces.