I suppose whether a screen protector is needed or not really depends on the user. Do you carry keys, pens, knives, needles, ice picks, razor blades, scissors, screwdrivers, or other metallic objects in the same pocket as your phone? Then, yes, a screen protector is needed. A screen protector is always preferred to protect the screen of any phone, and I suppose would probably be a pretty good idea on a phone with an exposed screen.
Just speculating, the N95 has the same processor as the N93 so I'd have to go with yes, it is just as fast.