VPN with nortel

I am presently battling with the decision of either purchasing 4 nortel bsr 252 routers to create a vpn to connect 3 locations to my central server where I work or buying one of the higher end vpn hardware such as sonicWall. Each of these locations only have one personal computer that needs to be connected to the network. The primary reason for this is to access sql databases that are located my server needed for entering data into a program. Two of the locations are not far away from me. Please post your comments on any technical knowledge you might have on what might be the best move in terms of, expansion, connectivity, security, pricing etc..