Id love to drive a T class sub, but for now im happy with the US subs availiable, im more concered about Japanese AI subs making it in to the game, I really hated being the only sub in the entire ocean in SH3, that really sucked (it was the biggest let down for a great game).
If SH2 can have AI submarines why cant SH3 and 4? Give me one good reason. As my sig suggests I want the chance to slam a torpeedo in to an I-boat and at least be able to assist/meet other US subs, even if there are no 'wolfpacks' strictly speaking.