I read this thread yesterday morning, thought about it, and spent the rest of the day at a site that I've only visited sporadically before--MTS2.  
I'm still just scratching the surface, but I've downloaded tons of free stuff I didn't even realize was available, and bookmarked dozens of artists whose work I'd only scanned before.
And I realized something about my downloading habits:  For me, it's not a matter of "this is better stuff because it's pay".  It's just been a matter of convenience.  I got into the habit of going to certain pay sites, giving a little money here and there, and downloading the things that appealed to me.  Why?  Because I was so eager to spend my limited free time playing that I didn't want to spend more time looking around for new sites to find free downloads, or plowing through huge sites like MTS2 to find what I wanted.
Am I ready to discard everything pay from my downloads folder?  Probably not--hey, I'm honest.  But am I going to be discarding a lot of pay stuff in favor of free stuff?  You betcha.
So I guess I'm learning 

  Not 100% there yet, and may never be.  But I can see having an 85-90% downloads folder that's from free sites in my not-too-distant future.