Is BuysellAds.com, legitimate?/anyone have any experience with them?

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I've just found out about this place recently and my TR from alexa is still quite high however it's quickly going down so I may be considering using it soon. However, their TOS, and other help sections are very vague which worries me. More in the case of legality, then legitimacy. With no solid foundation for their TOS they can get sued just like that and shatter into a million pieces. My question to you guys is are they legitimate, and for anyone who's used them how much success have you had?