So, the only difference is a slight height increase and a stronger pump, the dimensions vary as you can move the filter bag about 210 degrees left to right and this would change the dimensions. The quoted dimensions are without filter bag for this reason- 9415 13.8 by 11.8 by 17.3, 9430 is 13.8 by 11.8 by 19.3. The filter bag adds 4.5 to 9" depending on orientation.