The ramp works pretty well.  Some training was needed to get my dog comfortable with using the ramp.    

The biggest issues I encountered after two uses:  1) The ramp leaves scratches on the "car" bumper.  Placing a small towel between the ramp and bumper may protect against scratches.  The manufacturer should consider attaching some nonabrasive material to the portion of the ramp that will contact the bumper.  Or at least provide recommendations in the package for avoiding damage to the bumper.  2) Widening the ramp a few inches would improve the ease of use.

I rate the product slightly above average.  This two improvements suggested above would move my rating toward 5 stars.