Controller code.. your opinion?

[eluser]SitesByJoe[/eluser]
Method A. No one has mentioned this, but using style A allows for very exact naming in both your functions and your urls if that matters.

Using style A as it is above, you can have nice clean urls like:

http://mydomain.com/users
http://mydomain.com/users/add
http://mydomain.com/users/edit
http://mydomain.com/users/delete

You get the idea. Using your imagination a little, CI becomes one heck of a search engine optimization tool since it allows you to craft how your urls will appear.