Controller or URI Routes?

[eluser]jtkendall[/eluser]
Hi, this is probably more of a general MVC question than CodeIgniter specific, but since I use CI I figured I should ask here.

Right now I have a controller called "administrator" and I want all of the administrative functions to appear under the administrator controller in the URI. So I've been building all of my administrative functions under the one controller (and it's quite large). I read about the URI routing options (after I had spent a week on the project).

My question is, which is better from a MVC perspective and from a processing perspective. To use one controller with all of the grouped functionality in it, or to use multiple controllers and URI routing to keep the URI appearance?