Just be sure and check their feedback, and be aware that you'll most likely be paying a bit more. I bought my 3rd gen iPad from a marketplace seller (only because I was using my Amazon credit card). The best way to purchase through the marketplace is to order from sellers where the product is "fulfilled by Amazon". That way, even though you're purchasing technically from a third party, the item is actually coming from Amazon's warehouse and you are entitled to all the Amazon perks (like Prime shipping). In a nutshell, it's pretty safe to purchase through the marketplace. I've done it many times without a problem.