The speeders aren't usually a problem in good weather, you can just let them go. A pet hate though is the drivers who set the cruise control to 169kph (the point serious legal consequences start) and start flashing from a kilometre away, take 5 mins to reach you and if you get out of their way another 5 mins to pass. In bad weather it can be pure looney tunes around Milan, these drivers are in a hurry and won't slow down for details like peasoup fog, blizzards or deluvial rain. I am certain these guys are driving blind as I have good eyesight and I can't see well enough to drive at half the speed they do.
Like you. I got a great deal of satisfaction two winters ago when it snowed on icy roads and Milu drove me home in his car as he had chains, we were passed by a 4X4 going hell for leather and causing chaos for others by making them stop while going uphill (on a road like an icerink!) The satisfaction came when we saw him in a ditch with little chance of getting towed out for at least several days.
When I first moved to Italy I was shocked when I was passed on the Autostrada by a driver doing at least 40kph more than me and reading a newspaper at the same time. Drivers in Italy need and seem to have much faster reactions