The reasons KazaaLite K++ is better, I like the way you can customize that auto search function, it can even be set to just keep on searching like WinMx does. This way you get plenty of sources. WinMx still works but not that many are sharing on it now.
Another good p2p to learn for music, is Soulseek.com. It's a little trickier to learn but it may be the closest thing to the newsgroups but still p2p since you can request certain files in the various rooms and someone will usually help you get it as long as you are sharing files (at least 300) with the Soulseek community. I use this p2p for jazz since both Kazaa and WinMx are weak in the jazz area. Soulseek will get you ANY kind of music you want. Soulseek reminds me of the late great AudioGalaxy.com, which was probably the best p2p EVER even better that Napster. On AudioGalaxy I found music no other p2p had. All you had to do was go on their message boards (which are still up) and ask for a song or album and someone would come back and get it for you. AudioGalaxy was amazing!
Emule is an upgrade of Edonkey which was loaded with spyware just as regular Kazaa. Not sure if emule is spyware free.