I tested beta 3 and now trying out beta 4.
Updated two pc's. One and older machine 300mhz hp desktop. All went fine with the upgrade.
The other is a toshiba laptop, this one gave me trouble. I tried the upgrade but after the reboot the service would not start. I have to uninstall with the revo uninstaller and reinstall.
After that it finally worked after I removed the service from the registry before the reinstall.
Performance seems about the same. removed and readed the cache on both. Seems to work like before.