Well, according to them:
Authenticity Guarantee
We proudly stand behind the authenticity and quality of all merchandise sold on our site. We guarantee each and every product offered for sale on our site to be brand new, genuine and authentic.
Our merchandise is the same as those sold in the respective designers' or brands' boutiques, except that we are offering them to you at substantially lower prices. All our merchandise is purchased from reputable resellers and authorized vendors with whom we have established enduring relationships.
DesignerLuxury further guarantees that all merchandise sold is free from defects and in good condition as all items are thoroughly checked before delivery to customers.
To ensure safe delivery, your order is carefully packed and sent by reputable courier services with tracking information and is insured against loss or damage during shipment.
If for some reason you are not totally satisfied with the product you receive, we have a 30-day money back guarantee return policy if the purchased item is returned unused, in original condition and packaging as received, within the 30-day period. All we ask is that you inform us within 1 week of receipt if you would like to return the merchandise.
But they don't even have their own checkout system - they use PAYPAL! This makes me nervous and it basically screams "fly by night." So who knows if the site will even be up in 30 days.