I think they have missed a trick.
Why is is necessary to run the record engine on the NAS? What's wrong with running the record engine on the network-attached tuner unit and telling it where (on the network) to store the recording? Possibly they have envisioned the PVR element as a bit of software that runs independently of an existing network tuner, but it seems to me that a software upgrade to the network tuner would be more effective.
Why does there need to be a dedicated app for accessing the recordings - won't any media player (capable of accessing network storage, and TS-compatible) do?