I haven't seen a box of "Silvertip" ammo, of any type, for over 15 years. It may even be longer since I have seen them available. When I was the range master for my department I bought Silvertips for the calibers allowed. These were .38 special (125 gr), 9mm (115 gr.), and .45 ACP (185 gr.). Never had a shooting with them. I felt though that we were using the best that Winchester was producing. I believe that they were the product of the best technology then available.
But, technological advances have produced better rounds now I believe. Although I think that the Silvertip ammo is still a good defensive ammo it has been surpassed by the new Winchester Ranger line of duty ammo which has the "SXT" bullet (which looks remarkably like the old "Black Talon" of years ago which is what I replaced the Silvertip with). The now used 127 +p+ SXT is what my current department uses, as well as the 230 +p .45 ACP and the .38 special 129 gr. +p.
The old Silvertip was a good round. I feel very strongly that the round suffered from very bad publicity in Law Enforcement circles in this country after the FBI shooting in Miami in 1986. Very unfortunate but the one 9mm Silvertip did its job. Unfortunately only one round was a hit.... None-the-less, the ammunition manufacturers were spurred on to produce a better round and we are seeing these now in the CCI Gold Dot. Winchester's SXT as well as the other makers. It's hard to know if anything can surpass what is now being produced. I have a few boxes left of Silvertip duty ammo. I probably should shoot it up.