Taking a look a the chassis, it seems to be an evolution of the DF series in the farthest sense. Gone are the rounded corners and elaborate industrial look. What has remained is a lot of metal mesh, straight lines and an overall edgy look. In terms of construction quality, the plastic does not leave anything to be desired and the metal mesh in the front is thick enough as well.
Taking a look at the front, the interior of the case can be seen shimmering through the metal mesh parts. In the rear, there is a bottom mounted PSU bay and it should become apparent at this point, that the Eleven Hundred has an all black interior.
Antec has done a very good job with both side panels. On one hand you have a thick acrylic window with two embedded slots for 120 mm fans. In terms of size the window is just big enough to show you the most from your system, but not the drive bays. Antec has done an excellent job incorporating the cutouts for the fans, but I would have still liked to see a built-in dust filter here. The other side has been extruded slightly and also has an air vent right where the CPU cooler underside would be. You may install a 120 mm fan here to keep temperatures down if you wish. By having to place the cooling unit unto the side panel and not the mainboard tray one keeps the area free and the backplate accessible.
Taking a closer look at the front, there is the large metal mesh in the bottom. A fairly big Antec logo has been placed on the bottom edge of things. Above that are the three 5.25" drive bays and the I/O consisting of 2x USB 2.0, 2x USB 3.0 and the usual pair of audio plugs. I would have liked to see the addition of a 3.5" adapter to give the user the utmost flexibility to install whatever is needed.
In the rear, there is the bottom mounted, multi-directional PSU bay. You may install a power supply with the fan facing up or downward. Above that are the nine expansion slots, as this is an XL-ATX chassis. There are two openings for water cooling in the side as well, allowing you to route tubing out the back of the chassis. In the very top you will find a 120 mm exhaust fan, which does not have any LED or speed control. Antec would call this a "MonoCool" unit.
Just like with the P280, Antec has placed the power and reset buttons in the top panel of the Eleven Hundred, but unlike two 120 mm fans, you will find one large 200 mm unit here. This one features a blue LED which may be turned on/off separately.
A little panel has been placed in the top area of the rear, which usually allows you to control the fan speed of numerous units, but with the Antec Eleven Hundred, the only thing you may toggle is the power LED of the top fan. Having such a panel has been one of the unique factors of the manufacturer and I do not see any reason why they could not have included the full functionality here. There is a dust filter protecting the power supply, which may simply be pulled out from the main side of the chassis - just like in the P280.