I bought 3 of those monitors "Crossover 30Q5" 14 months ago. I had problems with them since.
I had to replace the AD board on 2 of the monitors within 3 months. When getting those AD boards I bought 3 more just in case. I'm a 3D CAD designer and I want all of my monitors to be running. So here I am today, I went thru those 3 AD boards and wanting to order some more, I have e-mail the company and I did not get any reply.
I hate the monitors, they are not reliable, one has a vertical pink line haft way thru the screen.
One has non uniform back lighting. It has 2 horizontal non running strips of light, I think they are led.
As for the 2 arrows you have to keep your finger in contact with the switch during a few seconds and then you will be able to raise or lower the brightness level.
It is the same kind of switch for the power. I just hate that type of optical switch.
Like Fatty said, they overheat very fast, I have to keep them at minimum brigtness otherwise they
All the informations I'm giving are up to my knowledge level and on top of that I speak french so excuse some of my may be not totally clear comments.
Please feel free to ask some questions as my reply is there to save you from buying those monitors.