I think so far we pretty much have a consensus -- these sites are somewhat good, especially if you have children you're trying to protect, but they're also slightly flawed in terms of how they designate who's an offender and who's not. I was taught as a child to distrust everyone until I knew them well. I watched a whole lot of slasher/killer-type movies as a child, so that was also helpful in teaching me a fair amount of caution and distrust towards strangers. I never forgot that lesson. Anyone you meet, ANYONE, could be an offender of some kind. Until you get to know them enough to feel the trust between you, reciprocated, it's best to be cautious of everyone.