I wouldn't worry about it. I don't think you'll ever notice increased engine wear. I doubt you'll every put enough milei on it to ever get to that point. I'm talking 150-200k miles. Ive run my civic for hours at 3600rpm at 78 mph. Still knocked down some great mpg! Only reason for the Od trans is noise, peace of mind and some mpg gains. Im doing the od in mine too, mostly because I can't stand to see the tach sit that high!