Question about PHP with fastcgi

[manarak]

I read that security of PHP is greatly improved with a fastcgi implementation, since then scripts would not run under user apache but under the script owner's username. This would allow safemode being turned on for most scripts (image galleries with image uploads, nukes, etc.).

A side effect of fastcgi implementation is supposedly also improved performance, whoich can only be a good thing.

Now how is the compatibility with Plesk?
What problems could I run into?