I would prefer subtitles to voicing over. Most of their interviewees are non-English speakers, and I don't think they are doing a particularly great job in translation. Better to let at least part of the viewers hear what they really want to say.
This is a great effort in part of BWF/ING. It is a lot of work to produce a weekly video magazine like this, esp when each one is almost 25 mins long. There need to be a lot of research work done, as well as a huge production team travelling to various location in the world to interview the players and produce interesting material.
To be honest though, I didn't start watching it until last night when I had a long overnight drive home from out of town. Badminton Unlimited was the perfect companion to the drive because it was sufficient to just listen to the audio with all the interviews and narration. It was interesting to learn about LXR and Marc and Arvin, etc while I drive. And it kept me awake until 3.30am.
I do believe that in general, the issue is that each of the episodes are too long. It is ok if they are showing it on TV, but with short youtube attention span that most of the online population has, breaking down the video into <10min segment would keep viewers interested as well as getting more opportunity to generate more revenue for BWF/ING.
They upload it to Youtube almost a week later .. I watched the one that they uploaded today last Tuesday on TV. Here in India, the new episode broadcasts every Tuesday. In India, they broadcast it in English as well as in the regional language, Hindi.