Amazon is selling the Drobo 5N for $430 right now…not sure how long it will last!
http://www.amazon.com/Drobo-Storage-Gigabit-Ethernet-DRDS4A21/dp/B00AMAJGOO/ref=br_lf_m_7991333011_1_1_ttl?ie=UTF8&m=ATVPDKIKX0DER&s=pc&pf_rd_p=1662250582&pf_rd_s=center-3&pf_rd_t=101&pf_rd_i=7991333011&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1KXPZH7W3VGRX3E1GGHQ