Dale, I'd love to have a couple of the slitters you have. 99% of the time I'd want to use it to cut backing paper without separating it from vinyl. But maybe I'd use it to cut stripes, etc.
I tried someone else's suggestion of using an old knife/knifeholder, but could never get a consistent cut. Until I find a better solution, I'm getting ready to go to K-mart and blow 2 bucks on slitter Colorado linked.