To SK's point, if you live in the boonies, deals are far and few between. I was in South Dakota for a meeting and couldn't believe how little was for sale on Craigslist. I am sure North Dakota is no different.
As to the Icon boxes, I saw them in HF and the ones I saw, likely 4 months ago looked pretty nice, but they were unpriced. What little pricing I have seen on them, they are too high IMO. I agree with Highland, a used truck box can be bought for the same money.
As to US General boxes, likely good for a serious DIYer but I don't see them holding up in a pro environment. Certainly a good value to get started with though.
As to the latest CMan boxes, what a POS. Fine for a homeowner but even a serious DIYer would be disappointed after a few years. Saw one in the local John Deere shop yesterday and just shook my head.