With HD, you'll have to decide what kind of output you can support. Most will output either HDMI or USB3 and with either you'll have limitations on distance without converting to some other medium first, such as,
HDBaseT. If you buy a camera that outputs in
SDI, then you can carry that a lot further over common coax. You'll then need an SDi-to-HDMI converter, if you wish to put the signal into the VidiU box. There are also wireless HDMI extenders, such as
this one from Monoprice that operates in the 60 GHz band, but their performance is significantly reduced for each wall or ceiling passed through, so YMMV.
Once you've figured out how to get the HD signal from the camera to where you need it, you're ready to shop for an HD camera. Be prepared to have your SP spring at least $1500 for one with a smooth PTZ, good zoom range, and good sized imaging chip. Sony isn't the only game in town, but most of the PTZ controllers (both hardware and software) designed for the EVI-D80, will also work on their HD cameras.
Just some things to think about before jumping into HD.