Great question and sorry for the delay in an answer. I used the same exact drive in testing of both of the NAS boxes used in the review. I also contacted Synology to reassure that my assumptions were correct that the DS207+ is exactly the same on a hardware level as the DS107+. We did not have the DS107+ in house at the time so instead used the 207+ with one drive installed.
Let me attempt to inject a little personal opinion now. The QNAP TS-109 Pro is a great example of what a good NAS should be. Performance wise, it couldn't exactly stand up to the Synology but for a majority of all users, this won't be hindrance. I am currently testing the 207+ and hope to have a review up shortly on it's performance. The hidden gem though in Synology's products is undoubtedly their software. Offering most everything that the QNAP's user interface offers (with the exception of the potentially life saving network recycle bin), the Synology UI is far more polished and user friendly. This might not effect someone like yourself who sounds like they know more than the average user considering your idea of using freenas but I like the new AJAX interface.
If you build something, post it here, I would love to hear about your experiences with whatever path you choose to go down.
