ResearchGate and Academia.edu are social networking sites for academics and are wonderful for connecting you with future colleagues and collaborators. However, as the librarians at Loyola Marymount University point out, "ResearchGate and other academic social networking sites are commercial entities that can use your address book and personal data for non-academic purposes." Additionally, ResearchGate charges users to generate readership reports, and the terms of use for Academia.edu grant the site permission to translate your work and profit off of it without making you aware (source).
SelectedWorks is a true research management service that provides valuable analytics to you at no personal cost. Though supported by NEIU libraries, your SelectedWorks profile remains available to you even if you continue your career at another institution. SelectedWorks also offers stable archiving of your work.