Thunderf00t: click here to viisit the channel
He is a chemical engineer from the UK working at a nuclear plant. He discusses topics like feminism, ridicules hoaxes and mostly famous for his "Why do people laugh at creationists?" series. I highly recommend this last playlist.
DarkMatter2525: click here to visit the channel
This one mainly consists of amatuer cartoons that present the logical controversies that the judeo-hebraic god's existence implies. I recommend the video God's God from his channel.
TheAmazingAtheist: click here to visit the channel
This is an american youtuber who argues about a wide variety of topics: human nature, atheism, cretionists, morality, ongoing events in the world, global warming etc. He is also a writer, published a few books. Sometimes he is very annoying - in an entertaining way - and acts immature, in my opinion, however usually makes some good points in his videos.
There are certainly other great channels on youtube, I didn't had the time to examine them though. I must say that I don't always agree with these three either but they might be an eye opener for some jws if they could watch some of those videos.
What YouTube channels are you subscribed to in this category? I'm waiting for your suggestions.