I tried with a 50000 lines file and ST2 has the same line number compared to 2 others text editor.
However, I have a different version:
startup, version: 2219 windows x64 channel: nightly
You can try yourself by creating a new file, opening the console and typing these 3 lines:
e = view.begin_edit()
[view.insert(e, 0, str(i)+'TOTO'*50+'\n') for i in range(50000, 0, -1)]
It must create 50000 lines with each line beginning with the line number.