However, there's a lot out there manage by reputed managers like Hhampuz, yahoo, and Darkstar_. Do your own research and it will lessen your risk to choose gambling site.
A manager managing signature campaign for a site shouldn't be a basis on which you should trust a site nor does it implies "less risk" of getting scammed. I can give out many past examples where campaigns were runned by reputed and experienced managers and yet came out as a scam.