Mirage Source

I was messin around with quest data when I thought of something.
Would it be faster if the quest information was contained in its own system of files rather than in each individuals account files?
Also, say that the player has the ability to check their quest log to see what they completed, would lag exist if there were several people retrieving info from the quest files?
Basically Im trying to build the cleanest and quickest quest system.
Thanks for any help/suggestions/comments.

Just add quest flags to binary player accounts and it will be fast enough =P

Or do it the proper way and give each quest its own binary file listing the players that have started, are at certain stages, and have finished said quests... is the most dynamic =P

Well I'd like to create that second option. How would I go about checking for and adding players into the file?