I recently ( three days ago ) purchased a SRP 527w and have been using it in a mixed Mac/Windows network. The setup is currently primarily using defaults apart from enabling logging. While I was still able to access the internet with some applications, accessing web content appears to have blocked after approximately 48 hours uptime.
No web pages using port 80 were available and that included the router web interface. The router would respond to ping only.
Frmware is 1.01.09
On a different note. I have to say that I find it very strange that the supplied documentation doesn't advise setting up the router using the admin login. It was only after reading one of the comments on this site that I was alerted to this security problem. I also find it rather annoying that I appear to have to purchase additional support merely to be able to download firmware updates which are designed to give the device improved functionality.