I am looking for a bit of advice on the best hardware for an upcoming upgrade. We currently have a WAN with 4 locations connected via MPLS. The main office has a Cisco 2821 and the remote sites have Cisco 2801s. The MPLS handoffs are T1s and so each 28xx has a DSU/CSU WIC. We are planning on moving to a VPN over fiber infrastructure for primary connections to the main office, (the remote offices don't need to communicate with each other.) while keeping the MPLS at 1.5mbps as a failover network.
We're are going to invest in new hardware, but after doing a bunch of web research I'm seeing conflicting opinions and statements. So, my question is this:
Is upgrading to Cisco 29XX with the security bundle and DSU/CSU card the best approach? Or should I be looking into ISRs or ASAs?