Well...do we REALLY need any of this stuff?

Anyway, it depends on your budget and the level of accuracy you want to achieve. I've been working on my Fett suit for about four years, gone through several versions and upgrades, and only recently this year did I break down and buy the awesome chest display made by TK409's brother. I got to the point where my costume was complete and cool, but I just wanted to get to the next level of accuracy and coolness.
Since it is costly, I'd consider it a finishing touch, but if you're on a tight budget, I'd recommend putting your resources into more important parts first (especially a good bucket).