3.4 gave us pip installed by default https://docs.python.org/3/library/venv.html

Before that it would give you an empty venv, not even setuptools

Yes, you can use the Python 2 virtualenv on Py 3 but I remember that there were some problems

The usage is essentially the same, just a different command. Huge benefit though is that if you have Python 3.4+ installed you already have the virtual env and pip installed, so things are much simpler.