No, it's perfect. The Performance increased a lot since it has EFI.
The system performance feels very smooth, and programs open (even) faster than on Rev1.

System Updater told me that everything is up to date - iTunes and other Programs that I tested work nice.

It basically feels like the RC1 that I customized for a week or two to make it work nicely,
but much more smooth and faster, I guess that's because the stock kexts work very well together.

Edit: The processor load is now at about 4-8%, with the same programs opened Rev1 had 20%, wow!

Good Job!