I have the Apexi VAFC on my 92 there are some tuneing options with it but not partaining to the the VTEC. The Vafc is set up for 4 cyl cars the nsx having to banks and trying to hook up the vafc will put the enigne in limp mode, or this has atleast been my experience. I am hear NSX modified is planning on makeing a fix for this by inserting differen capacitors, diodes, and such in line with the Vafc's vtec controller.
What exactly are you trying to do? If you really want to optimize your fuel management, get a programable system like Haltech. If you have a modified engine, it is especailly useful, as you can tailor the fuel and timing curves on the dyno. I have seen totally stock Mustangs pick up 20-30 hp at the wheels just by switching to an Accel DFI and tuning the system well. Also, as you continue to modify your car, you can adjust the system accordingly.
The other plug-in solutions are a bit cheaper, but they are Band-Aids based on averages and guesses. Just my 2 cents.