Yu never know nowadays. Best way to find out is ask people that have used specific tools to know whats works and what doesnt work. What tools are you using? Even still, google has a way to not penalize some and go after others. I have seen huge drops in page rank because of such tools. I never chance it anymore. I do things the old fashioned way and advertise a few hours a day. It works and spreads like wildfire, just not as fast.