Cisco 7940/7960 with SIP firmware pre installed

I have found several listings on eBay of Cisco 7940s and 7960s with the SIP firmware already installed. If I purchase these for my office, will I be able to set them up with my FreePBX server out of the box, or will I still have to flash and set them up to work with SIP?

Here is a link for the listings:

THe 7940 and 7960 are one if the simplest phones to change to SIP and configure as they use simple flat files (no xml).

I wouldn’t be scared of any of it, the free endpoint manager take care of this for you anyway.

Thanks! I just ordred several 7940s and one 7960. When the phones arrive Thursday, all I have to do is point them to my TFTP server right? I have already configured all my settings of these model handsets in End Point Configuration Manager. Also, what do I put for my Services and Directory url and, does the logo have to be a certain size or image format?

Thanks, Parker