This could work depending on the no of site to site
and vpn remote access you are configuring. The VPN 3000 is geared for remote access and it could also handle site to site vpn. The Cisco routers are geared mostly for site to site vpn connection. You could use a combination depending on your requirements. A good place to start is with:
http://www.cisco.com/warp/customer/779/largeent/design/vpn.html
Then the relevant data sheet of the VPN concentrator on:
http://www.cisco.com/warp/public/cc/pd/hb/vp3000/