I find pin basting to be troublesome when I am actually quilting. Too much to work around. I use spray baste, painter's tape to secure the corners ( I secure each diagonal corner first.) I spray the bottom layer first and work up to the batting and top layer.
I usually spray half of each layer at a time and then it's easier to smooth the wrinkles out. Works for me! If you are doing a large quilt, it helps to have someone opposite you to help keep the quilt fairly taut.