Well that's about the extent of it. Once running and broken in, what's the difference? lol And as for the price, EDMs are still cheaper than rollers. I HAVE EDMs in the Ford 400 I have ready to go in Gladys. I found them on sale. Well.....they're technically NOT EDMs they are Crower Camsavers which have a flat ground into the side that puts pressurized oil right on the lifters. But you're right. I'm sure they're beneficial during initial startup and break in.