It's worth having them. Just take your time. The kit comes with 9 grades starting at 1500 grit. You need to work each area in one direction then the opposite. I started first couple passes with horizontal and then did a couple vertical passes. The next grade started horizontal followed by vertical. Do NOT work in a circular pattern. Each finer grit paper should be done in a slightly larger area so you fan the sanding out and blend it into the surrounding area for a smooth transition. For deeper scratches you may want to get some 400, 600 and 1000 grit from the autoparts store and silicone it to a cleaning pad for your magnet. That's what I did and the stronger grits worked out great for the deeper scratches as well as areas that were more scratched. While this job isn't for the faint of heart, the effort is well worth it and if you take your time, the results are amazing!