I have used fighters very little. I prefer the "capital ship" model of space warfare.
But, I have used them a few times just to see how they work. Yes, fighters can move independently within a system. That makes them the one unit that can defend an area instead of a point. There are some quirks with launching and retrieving them. I wish you could recover fighters in combat, for example, and it seems that they cannot move on the system screen (strategically) immediately AFTER being launched so you have to launch them the turn before you intend to attack. That's no good for surprise raids!
Especially if your carrier is cloaked in enemy territory. So, there are some things I wish could be changed with fighters, but I have other concerns first.
[This message has been edited by Baron Munchausen (edited 28 November 2000).]