I assume that the NewTek control surfaces use a proprietary protocol so they cannot be used. Apart from the flimsy plastic T-Bar it was close to what we are looking for but it still looked like a prototype knocked up over a weekend in somebody's shed. I did see a unit at IBC this year on the stand which I think was called X-Keys.
I have seen that some users are using MIDI audio surfaces but these don't really arrange the controls in a way which is familiar for those of us used to working in traditional broadcast environments. are too prone to errors in a live environment. However what I cannot find at the moment is a suitable hardware control surface to use. We are currently evaluating vMix as an alternative to the NewTek Tricaster and at the moment all is going fairly well and it looks very promising.