Hi Dobly,
I tried to wade through their site before I found the Karaoke-Version page, and it made me uneasy. Not sure about the payment integrity. It's a bit hard to tell if the songs are true stems from original sources or are covers. Some are listed as covers, but others are just the name of the song and the artist. Seems like it might be shady. The sheer number of songs available make me think that licensing and copyright protocols aren't being followed. Now, some of the songs available on the site I use (
www.karaoke-version.com) are kinda off, but they generally do a good job with a cover and it's fun to be able to drop out various instruments and play along. I usually download a full version of the song, then a drumless with a click intro. Now that I'm getting used to how AD2 integrates into Reaper, I might download a drumless with a separate click track and send the click to a monitor out, but not recorded. You only pay for a song once, and can download as many versions/remixes as you want for $2.99 US.