In the case's favour,
* It has Slide rails for the 5.25" bays - but there are 4 holes in
each side of a 5.25" device, yet the slide rails only use the bottom
2, and you find that out by trial and error (it doesn't work in the
top 2).

* It has removable trays for the 3.5" devices - FANTASTIC

* There is also room for loads of 3.5" devices, all in removeable
trays, and beautifully located so that a front fan can blow air over
them. - Wonderful

* Removable FDD cage with a latch - GREAT

* Antec - I believe - do sell extra drive rails if need be.

Cons
* The side of the case is almost a gimmick. It has a locking mechanism
which doesn't do anything because you can actually take the side off
very easily whilst it's 'locked' (though the gimmick lock doesn't
close properly when you do that - it breaks easily) It's a very cheap
side.

* The 5.25" rails, aren't so great. They are sturdy - the drive won't
shake in there, but they can screw in into many different positions
whilst only 1 position works. So that can cause some annoyance, since
the correct position must initially be found by trial and improvement
- and by example thereafter.
And they only make use of 2 holes on the side of the drive, not all 4.
Really Antec should have let the case have nice Trays for 5.25" drives
like they have with the 3.5" drives.

* The front of the case is a joke. I like to look at the front of the
computer and see what drives are in there. On this case, I have to
open a door to see. How stupid. And when you open the door, you see
an ugly thing, metal framework with holes. It probably has to be
closed to retain good airflow.

* The case does not support thumbscrews - at least not in the 5.25"
bays or the 3.5" bays. So if I want to unscrew or scrwe in a drive to
the rail or tray, I have to use a screwdriver. This is forgivable
because no manufacturer i've come across provides slide rails/trays
WITH thumbscrew support(since the slide must be a tight fit, there is
never any room for a thumbscrew, and at least there are removable
trays or slide rails. So you won't have to unscrew the drives that
often - unless you want the drives in another computer/case with a
different design.

------------
To conclude,
the ability to slide 5.25 and 3.5 drives in and out is such a valuable
feature, that they outweigh the cons.
The drives in the floppy cage don't slide in and out, but the cage is
removable with a latch, and one can probably use thumbscrews to attach
the drive, so it's not a big nuisance.
I have seen drive rails available separately from antec, so I expect
antec would provide extra packs of drive rails compatible with this
case if need be. That, of course, is another valuable advantage.