Apologies, All.
I'll need more time to test. I don't think I'll be able to get back to this and/or provide logs until this weekend.
I'll reconfigure my local pfSense so that there is a spinning disk device to which it can log. I'll then look at what's going on.
I do have a very large pfSense built out of an Dell 1850 Series 2 at work. It is an egress router for our 100Mb/s service in front of 6 TMG Gateways. It does have 2 of it 5 nics configured for NAT, however nothing is currently attached - they are for testing. I'll attach a simple linux device [likely CentOS 6.5x64] to it tomorrow and see if I have trouble rsync'ing there. I was going to complain and say that rsync works through the Dell 1850-pfSense [and subsequent TMG firewalls], however its configuration through which I'm rsyncing at work, is only routing, and not NAT. I need to test rsync through NAT.
Again my apologies. I'll have some relevant testing for you guys to look at either tomorrow night, or this weekend.
Thanks for your patience.
Ryan