The only difference between 'mens' and 'womens' hair colour, is the photograph on the box. The ingredients are virtually the same and there are obviously many more shades in the 'womens' colours. They just make hair colour for men so that they don't feel self concious buying womens' hair colour!! Clairol Nice 'n' Easy or Movida (can't remember who makes it, possibly L'oreal) will cover grey. I think you should choose the shade very carefully, as a man with very obviously dyed hair can look ridiculous! Having said all that, I do think that men with grey hair look great and as Smudge says, you'll have to keep re-colouring it every few weeks. What a pain!!!