I have sharpened both and A2 has quite a bit more wear resistance. The simple chemistry behind this is that A2 has more chromium, which increases its wear resistance. The same element is responsible for the larger carbides in the matrix of the steel that you see chipping out. With a powder metal steel (any of the CPM variety), grain structure is refined and carbide growth is limited. At least one old school steel, AEB-L, also has very marginal carbide development. Chromium carbides in A2 will tend to separate from the rest of the grain structure as a whole, and the chips will be bigger than typical "micro-chipping" seen with smaller particles in steels with more refined grain structure.
That said, once an edge has been optimized for your use, both O1 and A2 should be easy to keep up in the field. When honing a knife on a diamond or a ceramic or even a rock, we tend to slightly increase the edge angle in order to align the very apex of the edge. I would expect field sharpening to increase edge angle by at least 2 or 3 degrees total. So, if a knife comes out of the shop in A2 at 50 degrees inclusive, then 01 will seem easier to field sharpen because the decreased wear resistance will permit a little removal of the secondary bevel leading up to the cutting edge, and you might actually get away with keeping the angle consistent or even reducing it a little compared to A2. But if the knife was thin enough to begin with, most field-level stones would align the edge no problem, and the increases in angle from field sharpening would create a bevel that is still well below most production knives.
In simple terms, if your edge is sweet right off the bat, it won't matter in the field if it is 01 of A2, since you will only need to hone it. If it is too thick, 01 will be easier to sharpen in the field because you will be able to remove metal behind the edge just like you would sharpening at home.
