Why the regret? An archaic 3 years contract (hard copy to send by post to Spain like in the 19th century), no possibility to remove pictures by the contributor from his own page, no exposure, no sales and a messy and not very nice agency.
Better make money with exclusives than nothing with non exclusive in my opinion.
For example, I can't take my image to Getty from them (as Getty wants only exclusive) as I have to wait the end of the contract to do so.
Fortunately, I haven't sent too much pictures and I haven't sent the best ones there...