Not make much difference on my bike at 12.5Kg's, I dont have a problem in the wet with the gatorskins, maybe I just dont push as hard in the wet.Tyres are subjective, but I'm largely in the Continental camp when it comes to tyres with my favourites being Continental Grand Prix (lots of grip, reasonable puncture resistance if you stay away from glass strewn urban routes but they do wear sooner) , followed by Continental Gatorskins (less grip, especially in the wet, better puncture resistance and much more hard wearing), there is little weight difference between them though.
But.... but I though Vittoria was Italian, and I'm pretty sure Continintal are German...... Wasn't aware either of them came from Scotland....