Boris and bushinc,
Thanks for your replies. I don't have any experience in doing this sort of thing - I was kind of "appointed" to the task as I'm the most knowledgable in the office

For e-smith, I was planning on using FreeS/WAN since I know IPSec isn't supported be default. But, the more I think if it, it's actually less expensive to go the VPN appliance route as the other 3 locations in question do not have hardware yet for an e-smith machine.
We've had our SnapGear unit working here as a firewall/gateway/PPTP server for over a year and it's been rock solid.
IPCop sounds intriguing, too, as it's frequently mentioned on these forums and definitely bears a closer look.
Whatever route I take, I'd like to use a homogenous solution for all 4 locations as this makes deployment and management easier.
Again, thanks for contributing based on your experience. That's what makes forums like this so invaluable for someone like me.
Keep the suggestions coming!!