The main thing about a vg200 is that it can only have some voice interface in network module 1 and the ethernet in network module 0. So the vg200 can not be used for routing over the wan or something like that. The only things it is used for is a voice gateway. If you need to WAN routers to route traffic over the WAN and such then you can probably use 2600 or 3600 then you can just add a voice module to that platform to make the router voice enabled. So the only time you would use a vg200 is when you are just doing voice.
Hope this helps,
-Mckee
