The worst thing about WinMX's IM functionality is that you don't usually know when somebody wants to talk with you. I have my systray always in autohide mode so the only way for me to see that somebody wants to communicate with me is to have the hotlist window somewhere visible - like I had no better use for my limited screen real estate. If I remember correctly WinMX's privacy settings also default to you accepting IMs only from your hotlisted contacts and up/downloaders which is a bad choice for a default. It was/is easy and quite reliable to establish an IM contact between Napster and audioGnome clients whereas WinMX users are mostly unaccessible.
- tg