I've never heard of that site.
Their page has a bunch of chinese made parts in it, as well as images taken from other sites such as the windshield glass image from the AM general site, with being almost doubled in price. Another example is they have images of the Alpha Custom HMC4 hard top, some taken from ebay and others taken from the Predator website, with no mention of Predator anywhere, as well as selling it for $5 cheaper. I don't know if Predator has anyone they sell through in other states, but I would at least expect some type of mention of the manufacturer. There are other examples of this as well.
Pretty much every legit company at least puts a little info about who they are.
Also, the whois lookup turned up a canadian domain host with zero other information. Website domain was registered 1 year ago, so pretty new.
Not to mention everything is labeled in "USD" for pricing, which usually indicates it isn't really run in the U.S. as a U.S. site for the U.S. marked doesn't need to specify that everything is in U.S. Dollars
I'm not saying the website isn't legit, but I have doubts.
EDIT: corrected one brand name