Thought I would post as a deal the process I've documented in the comments of the original TGG Boxing Day deal.
To me this is a deal for those wishing to upgrade the capacity of their PS4 by replacing the internal HDD. In terms of pure storage per dollar value, there are other options (e.g. the 3TB version) however these are not necessarily guaranteed to fit inside the PS4. The 3TB example I linked to is physically too big.
Price is $99 at TGG or price beat at Officeworks (which is what I did) for $94.05. For reference, recent deals for this HDD have been $95.20.
The drive is guaranteed to fit snuggly in the PS4, and if you aren't too rough with the stanley knife, you can put the original PS4 drive back into the casing and use that as a spare portable HDD. I used this video
Original deal: https://www.ozbargain.com.au/node/284350
JB HIFI is selling 2TB Backup Plus for $95.2 (20% OFF $119).