I don't think it's DRM, judging from Sub's homepage - it looks like they use a streaming service for their videos, so you'd need to grab all of the segments, concatenate them all together, then possibly re-package them as something other than '.ts' (transport-stream) like '.mp4' for example...
...but the segments of those homepage videos are only a couple of seconds long, so to do that with Sandy's 25-minute vid with Christian, that'd be 600-800 segments, approximately.
I've done similar with short 30-segment vids, using Firefox to get the stream-URL's then something like 'Curl' to grab the segments sequentially, but nothing this large (or expensive to intercept).