I believe its dxlevel 95 not dxlevel 91

According to the command ingame, 0.1 - 179.899994

Its using an ARM processor so its pretty much your phone/tablet with no screen. Considering most tablets have support for mice and they are just as powerful there is just no point for this. If it had a low power atom or similar x86 processor it would be much better, but still not much of a use.

EDIT: website: http://mouse-box.com/
EDIT2: It would also be nice if they offered more information on the device, they have a prototype so it does not make sense why they wouldn't. However from the video it seems they are using a Texas Instruments chip and not much ram as I can only see a single chip (512MB?).
EDIT3: Ram is a Micron D9PXV part which is 512MB
Processor is a TI XAM3359AZCZ100 part which is a single core Cortex-A8
Flash is a Micron JW896 part which is a 2GB Nand

It appears this is actually just an older revision Beaglebone Black development board in a slightly different format

BeagleBone Black

http://i.imgur.com/wgtUTcQ.jpg

Mouse Box

http://i.imgur.com/RTk6uWJ.png

This means that the prototype is not the design for the final version and that they haven't even developed a final version with a quad core arm and 128GB flash chip. Seems off that they would put out specs that they haven't seem to have tested yet. The processor on the prototype also only supports 2 USB 2.0 ports (Datasheet) yet it has 2 USB 3.0 ports and I dont see any other chip that would provide that.

EDIT4: Also in the video they (Video at 2:12) they are measuring the voltage on a Raspberry Pi which does not make any sense at all. This all seems fake, from the claims to the video.

EDIT5: They had another video on their facebook page which showed a different prototype with it functioning. The prototype appears to just be a Beaglebone Black upside down in a mouse shell, matching HDMI port expansion headers and mounting holes.

Prototype

http://i.imgur.com/a1RxYKy.png

Beaglebone Black underside

http://i.imgur.com/SrbDrgu.jpg

https://twitter.com/DreamHack/status/538686133992177664

Goodluck LDLC

Just tested that as well, it being slightly darker is fine I barely noticed it. Just leave it as is so people can use whatever style they prefer.

Thanks f_blue for the quick update. And Paals according to rays

It seems to be a tf2 issue not hud issue.