Thanks for all the response.
The timing for 1 minute still seem sucky as our machine do 1 minute more or less. Although I have ran a extensive debug mode, haven't figure out how to read it. Any help would be great in deciphering it. From the timer, it seems to hang for like 30 seconds on one group policy. This is still cryptic to me UserEnv Debugging Line by Line - Rich Peckham's Technical Blog - Site Home - MSDN Blogs.
For mandatory profile, I was unable to replicate this Mandatory Profiles Solution for Windows 7 | K-5 Computer Lab with the profile stored locally. It maybe that it can't be done.
I'm guess everyone mandatory profile is not a local one, if so I have tried a few guidelines to follow upon googleing, but none yielded any fruit, just a temporary profile, and one situation where it was not working at all. I made ntfs permission to Everyone, and in registry permission too. Any other pointers about mandatory profile, although it doesn't seem to be of any benefit since we use deep freeze. Unless it may shave a few more seconds off.
More or less this is my situation: Specify same User Profile location for all users