600 HPS Should I buy this brand??

Is this the knockoff version or should I buy this light
http://cgi.ebay.com/600-WATT-GROW-LIGHT-600W-HPS-MH-Sun-VERTIZONTAL-ballast_W0QQitemZ280450555284QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item414c27dd94

Should I buy a better HPS and MH bulb?

Thanks