My understanding of cruise is that it keeps the needle moving at a fairly slow rate even when the machine head is not moving. It's useful when you are doing sharp corners, but not so much for stippling/meandering. I think it is probably dependent on the type of work you're doing. If you're zooming around and trying to form angles with the stitching, a higher number would be better. If you're doing smooth curves, it's probably better not to use it.