One thing to consider is that Panasonic won't let out the utility to get into "service mode" to do any tweaking or to fix any problems that might arise.
The method to get into service mode on NEC units is known, it just takes the included remote. I don't remember the common key sequence though. They also have reasonably extensive serial port commands too, do a search for "LT 150 PC Control" and there should be a PDF linked in a thread with that subject line.
If there's any chance that you will do presentations, NECs commonly have the PC Card slot where one can make a digital slide show without having to lug a laptop. Its usefulness is more tenuous for HT purposes, but one can keep test patterns in it for tweaking.