Network Ring

Dear all, I am in process of planning ring network to cover 15 POPs in City. Some technologies are chosen for consideration like SDH(Huawei), PVRST+(Cisco), RSTP(Zyxel), EAPS (extreme network) and MPLS(VPLS). The purpose is to provide L2 Ethernet connectivities from POPs to central point (DC) and ring protection. I know you all are in those network for years. can you give me some advises? Best regards, chanty