active without touch is awful, as soon as you stop having the button in the mouse pressed down the menu disappears, so its imposible use,
:) - hence setting :hover as well!
The main problem should be older devices as there was a lot of talk about developing the ability to sense :hover last year. The issue in the back of my mind is that the discussion centred on <a>'s which makes me wonder if it has been applied to other elements like <li>. That's one reason I haven't suggested :focus which is what an element should receive after a touch/tap. (The other is that it would impact on mouse users.)
So it will be interesting to hear how things work for your friends.