If you order the DVI kit, you'll get a DVI module which you have to install in the screen itself.
That will be a (HD) input.
You'll have to enter the service menu to change some settings. You have to tell the system in which slot the DVI module is placed. But as far as I know (i did order the module) the dealer normally has also to update the software of the panel itself. I don't know what it does, but with my it works without the update.
Along with the DVI module you'll have to assign a Scart/component or camcorderinput for the audio.
So, you'll get the possibility to name a scart (in US the componentinputs) as eg a DVD/DVI, or VAUX/DVI etc. Then the audio goes through the scart and the panel switches to the DVI input if you give the DVD/VAUX instruction.
But you only get just 1 DVI module, so just 1 extra videoinput. With a smal DVI-HDMI connector, you can use hdmi cables and switchboxes.
One thing is for sure, you'll get a razor sharp picture.