My rule of thumb is "If the deals look too good to be true, they are."
And based on that standard, there's no reason this site wouldn't be legit. Like the owner who signed up to comment says, it's just an Amazon storefront, and none of the deals you're getting are any better than you'd get if you shopped the "See more new and used" section on Amazon itself.
The site owner isn't selling any of the stuff him/herself, just getting the Amazon affiliate cut if you purchase Amazon or Amazon Marketplace items through the site. It's no different than any of the Amazon affiliate banner ads or "Buy from Amazon" links on the web, it's just wrapped in a nice shell and filtered to only show certain products. When you "check out", you just hand the contents of the cart off to an Amazon cart, and check out from there.
I've set up something functionally the same with anime DVDs in the past--Amazon even has a tool to build and custom-skin your own store if you want.
Not advocating for or against buying anything through the site in question (again, you'd get identical deals shopping directly through Amazon itself), I just don't like to see people arguing something is a scam when it's almost certainly not when you look at how it's set up. Not saying that assuming the worst on the internet isn't usually warranted, hive of scum and villainy that it is, but that's not always the case.