There are some sites about which there is NO confusion and there are those for which confusion abounds aplenty!! 

One PTC site which I researched for my list of 'reliable and honest' PTC sites is - ONBUX.  Now, for this site, i have got such a 50-50 response from the fourms on the net, that I'm going to use this site and see for myself!  Of course, I'd follow my own rule - NO INVESTMENT till I feel comfortable.  If you have any experience to share about this particular site, please let me know.