Ladyghst915 has a point that is sometimes lost in this new wave of costuming. Whereas before costumes like the biker scout were actually worn by human beings, clonetroopers of all shapes and sizes were all digital creations. Not one suit was ever made in real life. CGI armor was never made to be worn by real human beings. It can be aesthetically pleasing to look at but it was never designed to move with a real person inside it.
If you look at a clone trooper's helmet, for example, you will see that it is barely bigger than the head that goes into it. If it were a real helmet, it would be near impossible to wear. As a result real world clone trooper helmets tend to look oversized relative to the human body. They have to be to accommodate a real human head comfortable. The only thing we fans can hold that is the closest to the real thing is the Master Replicas clone trooper helmet, which was modelled directly from the CGI files ILM used and, even then, MR had to increase the size by 15% in order for people to get it on their heads. Even then, it's way too snug for people like me to wear them comfortably.
What this ends up meaning in the end is that some design compromises have to be made when crafting armor based on digital models. Sometimes the size, or the curve or shape of a piece of armor has to be modified so that, for instance, it doesn't pinch or cut the wearer when walking around. Sculptors have to balance functionality with accurate design and it's a tough balancing act sometimes.