sfx2000
Part of the Furniture
I’m using pfSense running on a Qotom i3 box; works great. If you go with Sophos or Untangle, you can get away with one of their less expensive Celeron 3215 boxes. The 3215 has better single core performance compared to the popular J1900 which helps with OpenVPN performance. An i3 of course is better as it also has AES-NI onboard.
Just note for pfSense - the 2.5 release will require AES-NI, so whatever chip one chooses, ensure that it supports AES-NI...
Neither the J1900 nor the 3215 Celeron have this instruction set...