I'm sure....!!!

The keyword here is not recomended. It is COMPATIBLE! See the above advertisement and you can see the words. Please bear in mind that ASSStro is a money making company, and besides the piracy issue on recorded material, they must have some tie with WD on this. WD also produces many external HDD range. Notice that it mentioned "MY Passport AV" HDD. I have an inside info on this. And WD factory is just in PJ right?

Assstro maybe use the soft word like "compatible" to say that "other HDD might not work". My Intel told me that they tried with other WD 2.5" HDD model but the decoder does not recognise it, except that one particular model.