I am looking for advice, comments and suggestions from anyone who has used Windows RRAS (2008 R2 Pref.) as the primary routers for our multiple offices. We have multiple physical office locations and are looking into utilizing Windows Server 2008 R2 Core as redundant Active/Active routers/gateways for our network as opposed to a physical router from Cisco or Juniper, it costs a lot less!
Any problems, issues or documentation anyone would recommend?
We will still most likely have a firewall on the edge but the majority of our traffic will be inter-office with some external services. We will be using multiple Class B networks across our two offices.
I'd never use general-purpose OS's and PCs for routers in a network with any kind of scale-- too many moving parts and points of failure for my taste. It would surprise me greatly that using a Windows host (or really, any general-purpose OS on a PC) would end up being cheaper, over the long-haul, than a dedicated embedded router. It may look cheaper, up front, but I suspect that years of applying Windows updates and dealing with hardware failures.
You can pick up used Cisco routers on eBay fairly cheaply. Get copious spares and you'll be good to go. (Whether or not it's "legal" to use them in production after purchasing them used is a topic for debate, I suppose. I think Cisco's attitude re: "transferrability" of their license is trumped the doctrine of first sale and is crap, but I'm not a lawyer.)
(Your use of the term "Class B" is dated, BTW. There are no "classful" networks anymore.)