David,
I've used them all, in an extensive, but empirical, sort of way.

Tmax100 (ei 64) is my least favorite. it has the best shadow detail of the three but I've always had a problem with blown out highlights. i've never been able to get a good solid print from it, ie, deep blacks, brilliant whites and everything in between. i always have to print a little soft to hold the whites. given your recent workshop with john sexton, I'd say that i've seen some of his original prints and much prefer the scale of his older stuff (like panther beach) done with tri-x professional.

delta 100 (ei 64) is not as fine grained as tmax, but pretty good. delta (100 and 400) always seems like an ultra fine grained tri-x 400 film. classic leica pj stuff with a good, soft tonal range of grays, never really capable of a strong white if properly exposed for shadows, but great for people shots. not the best for landscapes.

acros is my favorite of the three (ei 32 in sheet, 64 in 35mm, same film, but i compromise a bit with the roll film for hand holdability.) acros gives a great tonal range with good blacks, brilliant whites and almost as fine grained as tmax. acros BTW makes a bad print on AZO. I suspect that it is so fine grained, that you don't get the apparent sharpness of a contact print on BPF or Tri-x. xtol 1:1 is the best combo i've found. acros moderately enlarged on Bergger VCCB is my favorite small/medium format combination. but i usually need something faster like delta 400 or tri-x.

as long as we're hijacking poor roy's thread, I sent you an email a couple weeks ago but didn't get a reply. do you still want a couple of azo/rollo pyro grade 2 prints to show its possible to get enough contrast in neg for this combo? if so, email me address particulars.
tom