One of my favorite characteristics of TMax films is the relatively steep toe, and then the long straight line afterwards. This allows me to get
very crisp shadow separation in contrasty outdoor conditions, esp in the high mtns and desert, or selectively to distinctly block out shadows for a bold graphic effect, ala Brett Weston-ish. Conversely, where I want a more gentle gradation in the toe, I choose different films than these. T-grain version exists in a number of such options, and are basically just a method to give the silver more light-capturing surface with
relatively small grain. Then there are choices of speed, edge acutance, spectral sensitivity. There are a lot of wonderful black and white films to choose from at the moment. I use a lot of TMX100 and FP4 in the lab; and for outdoor shooting, a lot of TMX400 and ACROS, in formats from 35mm clear up to 8x10 sheets.