why use routers with voice gateways??

[admin_2]

In other words, could I have cisco AS5300 connected to PSTN via pri and also connect directly to another cisco AS5300 across IP WAN?

I see that cisco uses two routers on the WAN connectivity part, could they be eliminated if what's described above is done?

[#2]

There's no serial interface( wan link) on AS5300, normally you would be expected to connect the AS5300 to an edge router (25/26/7200) and then to the

other side.