I had a blender pencil and didn't like the results I got either so I put it away and forgot about it. One day in my local stamp store I ask the owner how a card was colored and she said using pencils. I was astonished. She showed me how easily it is done with the blending pencil. The key is to use firm pressure and apply a lot of color with your pencils when coloring first. Use the blending pencil to "blend" the two or more shades together. I think the blending pencil actually removes some of the color in the process and this is why it is better to deeply color it first, even with lighter shades.
Since then, I have enjoyed using my Prismacolor pencils with the blender pencil again. Hope this helps.
Daylene