A general question. Which printing paper do you believe can give the highest contrast. (Brightest whites and deepest blacks)?
At the risk of appearing pedantic, I'd suggest that a better way of phrasing this is 'which paper gives the highest Dmax?' because then you can't confuse it with e.g. grade 5 graded vs. VC. Nor can you confuse 'brightest white' with optical whiteners. Dmax, after all, starts out with the cleanest white the paper can manage and expresses the deepest black as a function of this, e.g. a Dmax of 2.0 means that the deepest blacks reflect 1/100 of the light of the brightest white.
Few papers greatly exceed a Dmax of 2.2 but I seem to recall that some contact and printing-out papers exceed 2.4. The slower the paper, the smaller the grain size and the higher the Dmax, as a generalization.
I've seen MG WT exceed 2.2 in the right developer, but with all due respect, I don't think it's an outstandingly meaningful question because I've also seen prints with a far smaller brightness range that give the impression of more luminous whites and deeper blacks, e.g. platinum prints. If the Dmax attainable is below 2.0 in a developing-out paper, though, I'd suggest it will often look flat and dull.
Then there's the question of separation of both light and dark tones: the whitest white and the blackest black are worthless if the tonality in between is no good.
Finally, I'd add that an immense amount depends on framing, lighting and (above all) composition.
Cheers,
R.