The biggest advantage is the ISO loader. Secondly, you'll have the usual features of 3.52.
There's an app called SVC for taking screenshots. It was made for an older firmware but it still works on 3.52 M33.
Guide for installing 3.52 M33.
http://forums.exophase.com/showthread.php?t=2732
And you can get update 4 here
http://www.psp-hacks.com/file/1231
And a guide for installing 3.52 m33-4 in one go.
http://www.stylemo.com/2007/09/14/ho...4-on-your-psp/
