Their business model seems backwards. There are a lot more of us consumers than producers, so why not offer packages to us? That model does turn SC into a more traditional service, but because it has a more unique collection than the alternatives, it seems to have distinct value.
I want to pay them, but they didn't seem to have a music-listener-focused subscription level last time I looked. All of their paid features were designed for music producers, not listeners.
Yes, the majority of people I know who are 'professional' electronic musicians/DJs have a pro account.
I pay for it and I'm not a pro. I really only paid because I wanted the spotlight feature and I also felt that I used the site so much it would be prudent to throw them some funds. Like most I have been thoroughly disappointed with the lack of upgrades to the site but so much good content is there that it's hard to walk away from it.
I use sound cloud for finding new artists and I don't even know what I could pay for...