unessesary upgrade in my opinion. I have also talked to GERRY @ PE RI and due to different tolerances of the pistons in relation to the PE stock one they can cause failure of the noid (more the LPR piston than the HPR piston) I single handedly experienced this.
My personal opinion is dont do it. Others have had no issues so I dont want to make you think that you CANT do it but there are risks with using Non-PE "upgrades"
The difference that I saw while the ETEK was working was minimal. Others have stated a Dramatic difference but in my case I did not see that big of a difference.