Since I haven't used them personally, I did a quick check for you and they seem quite legit. They have been online since October 2007. They accept safe payment methods and I was unable to dig up any negative posts on the net about them.
If you do have second thoughts about the authenticity of their products, you could always email them and ask for supporting documents to prove the authenticity of the brands they carry.
If there's anyone out there who has bought from this supplier, please feel free to let us know your experience. Thanks in advance!