http://armadaskis.com/ski-technology/
If you scroll down they will explain it in technical terms for you about the construction. But from my experiences and information from others, full sidewall gives you a smoother, more stable ride. Cap construction the sheet rolls all the way down to meet with the ski edge and it is more durable, although if you bust it then its harder to fix in the end than a full sidewall.
I would really just think, do you want to spend the extra money, and do you value the outside park performance alot because thats what the ARV is getting you. Having owned ARVs though, they are sick in the park man because the nose is really really soft and you can do alot of fun things with that.