After spending a year off and on POF, I've found that POF is probably 80% weirdos and losers, many of whom have criminal records. This was verified by police who told me to get off POF as it was full of men with histories - that they had many reports from women about men they met on there. I've had some very creepy messages from men, some just plain offensive, rude, etc - not a positive site at all a lot of players out there just wanting sex and lying about what they really want just to try to get into your pants
Pros
it's free and you get lots of messages
Cons
most of the messages are from absolute creeps or total goons who should be on undateables