Reilly, I will have to give the Cisco SPA series a good look. I got a few Cisco 7945s donated to me, and I am sure the work great with CUCM and Skinny protocol. I knew right from the get-go I would have to burn the SIP firmware on these. I grumbled about having to make available an TFTP (even though it is built in to FreePBX), but had to add the Option 66 to point to it.
I guess once you get it setup, and you know the ins and outs of the 7945G, it is not a big deal. It is just amazing that all the information that I needed to set these babies up was not in one place, but in about a dozen little corners of the internet. Google certainly is our friend.
When you say specifically the 7940, 7960 (and SPA) are supported for 3rd party call managers, I wonder what makes the 7940 and 7960 so special. Those models sounds like they are Cisco CUCM intended models. I can understand the SPA series being right out compatible. Cisco wanting to get in the SIP game across the board, regardless of the Call Manager, I can understand that.
Thanks again for your experience.