Yeah, the Silvertip lineup got a remake in the early/mid 2000's, according to a Winchester LE sales rep with whom I was speaking (at a hosted gel test event). When I asked why he wasn't demonstrating any of the STHP line, he said that the company didn't consider it part of their LE product lines, and that it typically exhibited shallow penetration compared to the rest of their Ranger LE lines. However, he also said that the STHP line had recently been refreshed, receiving some revisions, but since he didn't sell it to LE agency customers he didn't keep up on the engineering changes.
Personally, I never particularly cared for the original aluminum jacketed STHP, although I did favor (and still do) the nickel-plated copper jacketed 145gr .357MAG load. The aluminum jacketed stuff often exhibited easily deformed nose cavities during feeding in pistols, and the penetration was often observed to be at the shallow end of things. I vaguely remember when the original .44SPL STHP was revised to try and resolve some stabilization issues in some barrels. The 3" barreled CA Bulldogs I owned didn't really care for them.
On the other hand, the recent production 155gr STHP .40 S&W load is a real tack-driver in one of my .40's, a 4040PD.
Different strokes.
Come to think of it, the newer nickel-plated copper jacketed 110gr standard pressure STHP does pretty nicely in my 37DAO, accuracy-wise.