Add fur to skin of character with mirror modifier & weight paints.

I was pleasantly surprised to find that I could maintain mirror modifier on a mesh while rigging and weight painting, and also readjusting edgeloops at the same time! This short cuts the “trial and error” process of creating a character considerably.

Now I am up to the stage of adding fur (character is an animal). What are the things I need to be aware of in terms of workflow?

Can I add fur without applying the mirror modifier? (e.g. apply mirror modifier later on)
What is a sensible process of adding fur… should I ALT-D duplicate the skin and make the new one a particle emitter?

…how best to work? Basic steps please.