SEP Firewall vs. Windows Firewall on Server

We have a small network with a single server.  The operating system on the server is Windows Small Business Server 201 Essentials.  We will be creating another small network in another location soon.  The OS on that server will be Windows Server 2012 Essentials.  Both Windows SBS 2011 Essentials and Server 2012 Essentials come with their own (Windows) firewall.

We use Symantec Endpoint Small Business Edition 12.1 on the server (unmanaged client only).  We will also install SEP SBE on the new server.  Our primary line-of-business application is QuickBooks Enterprise.

Given what we have, would you recommend using the Windows firewall or the firewall that comes with Symantec Endpoint 12.1 (unmanaged client) on these servers?

Thanks.

John