Legit Site?

In Google search "3d model store" - you'll get links to this site as 4th and 5th strings. I think, it is not badly :)

I think the owners are aboveboard. They accidentally overcharged me and I didn't even realize, and they made a point to correct the billing error and personally contacted me about it.

However, the site does have droves of stolen models and improperly used IP, which is always a concern. As a seller you'd probably have no problem, but as a buyer, you really have to do your due diligence to ensure what you buy is legitimate.

This is my favourite site to sell models. Turbosquid is probably #1 on ranking but they take 40% of your profits.

this site is legal and good

Not being "U.S based" I don't fulfill your requirement, but you can always find traffic data here:
http://www.alexa.com/siteinfo

CGT's traffic ranks, as of 10.01.2018.

Global Rank: 6,612
Rank in United States: 6,783
Rank in China: 4,558
Rank in France: 4,630

You think "scams" are able to climb that high without being busted and prosecuted?