i have earned more then upgrade members from  almost 99% of PTC site ... 

daily earning $0.04 upto $0.30+ as a free members in Heed you where as i earn only $0.001 upto $0.008 from neobux to scarlet or other ptc site as a free members without referral ...
thanks you Heedyou ... hope this site will not lower earning for free members ...

and best site i should mention for referral is Pay4views.com though the site is new  i have got all my active referral from this site and i got around 30+ active for other site