Joe,
You can easily tune a stock pcm/ecu for nitrous application by adjusting a few constants, mainly its the PE constant, but the car will run like its being sprayed all the time.
As far as the pressure vs flow, yeah, I'd agree. Although it wouldn't be the injector, but more likely the pump. If the injectors had problems, the FMU and FPR's out there wouldn't exsist.
Atleast by utulizing the stock fuel system, your IPWs show an indication where you are at with your fuel system. With running a wet shot, there is no change in anything the computer sees, and your left to wideband or your narrowband ballparking. If you do a dry shot and use the ecu/pcm for fueling, its essentially as much stress on the fuel system as a wet shot. Dry shots have a huge following with SVT 03/04 crowd, as well as the gp crowd, because of what the nitrous can do to the rotors in the superchargers.
So what if Zex makes a show purge? If it sells it sells, You don't get into business to loose money.
One of the biggest dilemas is how nitrous flows compared to air, and gas. From what I've read, it flows quite differantly, and the intake manifold becomes the discussion.