Don't listen to these people. Go ahead and start using the program. It's a great way to meet new people; though, it helps if you pretend to be an underage nymphomaniac. (Just answer "no" if anyone asks you any weird questions like "Do you work for the FBI?".)
I already have AOL IM on my system as I use Netscape. Seems to work okay and we have it set up where just the family has access to each other. We never get any outsiders, spam, links, etc.
Never used the other program.