QUOTE(ZoidbergFry @ Jun 6 2013, 10:19 AM)
yep,love the rig,i also like a spacious back panel as cable management is very important for me,im currently using cm 430 and the back panel space is realy tight so i had to hide the cable under the hdd cage..kinda ugly when you open up the side panel to manage/clean the interior

Aha, you are a victim and a misguided end user. Worry not, many actually are.
Hdd cages first came in sideways but someone figured that you can save spaces rotating the hdd 90 degree.
So began evolution of the hdd bay #1.
Early variation of this layout had the hdd connector facing outwards. Easy access of the hdds. But then someone decided that it looks better with the hdd bay rotated the other way round so you won't see the clutter.
And so evolution of hdd bay #2 began. This design is commonly adapted. Two variation exist. One with the tray pulls out on the left panel, another with the tray on the right. Honestly speaking both are not very convenient and here is why...
Hdd connectors are on the rear (right panel) following current hdd layout. Regardless of how tooless and how easily accessible manufacturers made you think you still need to open the right panel to remove the panels and then open the left panel to pull out the hdd from the tray. (Most never thought of this because most assemble pc once and that's all. For those who build system and had to service pcs for a living, we noticed this some time ago.

So with the Enthoo Primo, if you want to remove the hdd, you open the right panel aka service side and you can do anything without touching the cosmetic side (left)
I do not remember who adapted this design first but LDPC uses the same design. Then then NZXT Phantom 820 also uses the same design.