My T is a couple of years older than me and having a T around my age is perfect! I wouldn't want someone significantly older or younger as I think that it's important for them to be able to relate to me. I can't imagine talking with someone significantly younger as they just don't have the life experience that I have or that someone older would have. My T is a blank slate so age really shouldn't matter since she doesn't disclose anything about herself, but I still like having someone around my age.