MicrostockGroup

So I'm doing a test. I have donated 3 old photos that sold quite good on other sites, but never on DT. Since I did this few hours ago and until now  one of the photos was downloaded 55 times, another one 38 times and another one 22 times. It's hard to say if it attracted some more traffic to my portfolio, because I haven't got sales on DT since I donated those 3 images. I am willing to continue to let them in the free section for a few days at least and see what will happen.
Anyone having any experience about some benefits from donating photos at DT?

I think you answered this yourself.  Don't give agencies free images.  It benefits everyone but the photographers.