I have the same opinion as Linda about my rotary blade sharpener. It seems to make the blades worse instead of better.
I've only been quilting for a short while, but have realized the best tools may be the duplicates (scissors, seam rippers) that I keep on my ironing board. I'm constantly searching under scraps and squares for these 2 tools. Keeping an extra set by the iron has saved me a lot of time.