Been installed since around 400,000 (while still in warranty and Cummins shop knew I did it). Engine now has 663,000 on it. I finally got a CEL little over 30,000 miles ago. Had it checked and EGR valve finally took a dump. Haven't bothered to change it since I have the block at the intake anyway. Other than that, no negative issues with doing it. But, there were several positive issues. MPG average went up .8 overall. Oil samples showed lower wear metal rates and, naturally, lower soot loading levels.