>Does anyone have experience with QNAP file servers, particularly regarding replication across the LAN.

NAS devices like QNAP or Synology are typically Linux computers with low-power ( e.g. Atom ) CPUs and lots of disk. They usually include Samba to provide SMB/CIFS file system/server capabilities for Windows clients.

I have some limited experience with consumer-class NASs from a few years ago. At the time their performance was poor, and they did not support multi-user VFP apps where the data were stored on them.

My understanding is business-class NASs are much better in performance and network support. As for "replication", that depends what you're trying to replicate. I believe some business-class NASs can replicate data between two ( or more ) NASs of the same make/model, but I don't know if they support replication between a NAS and a volume or share on a Windows server. Your best bet would probably be to ask on the manufacturer's support forum, regarding the exact replication scenario you want and the makes/models you're evaluating.