after seeing the "black widow" style intake with direct injection, brings me to ask; what disadvantages and or problems can result from this? would a bad solenoid be catastraphic vs wet kit into maf?

 

A bad noid would be catastraphic no matter what type of N2O system you run.

And by direct in jection im guessing your talking about Direct Port N2O? Its really the best way to spray b/c each cylinder is getting the same amount of fuel and n2o b/c its being injected right into the intake runner just like a fuel injector. Less flat spots and less change of one cylinder not getting enough of the squeeze and another getting too much such as a nozzle of plate system(carb).

 

A direct port will also let you tune each cylinder independantly....One thing to remember is a Direct port system is really meant for larger HP shots. When you start getting bellow 150-200hp the fuel jets are getting very small.

Typical single nozzle jetting 100hp 52n 28f
Typical EFI Direct Port 100hp........20n 12f (60psi fuel pressure)

When dealing with jets this small you must take the extra effort to make sure there are no obstructions present, when plumbing the system.

 

I am going to assume you meant a dry kit sprayed into the MAF.....there are problems assocated with any type of power adder. That is why you take the neccassry precautions, as with any power increase the car must be set-up and tuned for it.