We bumped up our Setup Guide for SBS 2011 after making two significant additions:
We added the post MFP step to configure the Receive Connector for the MFPs to 100MB.
We also added the step to use PowerShell in the Exchange Management Shell to quickly change the default message sizes for inbound and outbound e-mail.
Thanks to fellow MVP Rob of LAN-Tech for the pointer.
Microsoft Small Business Specialists
Co-Author: SBS 2008 Blueprint Book