PHILIPPO..........YES THERE IS A SMALL DIFFERENCE ,AS THE NEW PUMP WORKS ON DEMAND...... ,SO AS YOU PARK OR MAKE SUDDEN STEERING INPUTS THE GREATER THE ASSISTANCE FROM THE PUMP....IF YOU HAVE A MECHANICALLY DRIVEN PUMP IT WILL FAIL SOONER OR LATER ......BUT DONT WORRY YOU WILL STILL LOVE YOUR S1 AERO (YELLOW OF COURSE)...........SIMONG S1 AERO (BLUE IS BEST)