You all should look at some of the aluminum covers that are being made for the n55 now.
You should definitely replace the valve cover when you do this job. Otherwise you may find yourself doing the job again just to replace a squealing broken pcv breather.
The aluminum cover would be tempting for this reason. Easy to replace that part now without having to replace or even remove the cover. The rest of the valve cover will finally be reusable. With the aluminum cover, you can likely use sealant and possibly avoid leaks