Nitrous oxide vs Water injection - which one cools best?

[JohnA]

...Or more accurately, which one has the highest latent heat of evaporation?

I'm talking to a NOS guru and he insists that nitrous would far outdo WI as far as charge cooling is concerned. (gas is cooled down to -128F blah blah...)

But is this true, if we also take in-cylinder cooling into account?

Cheers