I carried various issued 3rd gen S&W's from '90 through '16. Calibers included 9, .40 & .45ACP. Once I became trained as an armorer for them (4 classes over time) I started buying several of my own, but they were all compact and subcompact, in all 3 calibers.
I still own the 3rd gen's I bought in those years, and I still own and use them, even though I also own other plastic and metal-framed pistols. I actually have more armorer classes in some of the other makes/models (i.e. 5xGlock, 5xM&P Pistol), but I also helped support some hundreds of the early 3rd gen Smith's, and then hundreds of the late production TSW models that replaced the original 3rd gen guns. I have some passing familiarity with them being run for quite a few years. One of the issued early production 6906's I carried for a little while ended up seeing upwards of a guesstimated 45,000+ rounds fired through it (although I replaced some parts and assemblies during that time). Another one only had a short time to be used to fire a little more than 3,000 rounds before it was time to turn it in for a new TSW.
The manufacturing and materials were improved quite a bit during the last several years of the 3rd gen guns being in production, and I especially liked the TSW models. That doesn't in any way mean I don't like my 3913, 4040PD, CS9 or CS45, though, even if they aren't part of the TSW line. (I also own a compact TSW each in 9, .40 & .45ACP.
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The 3rd gen guns have become designated as "obsolete", though, so it's becoming more difficult to get access to all of the parts. The smiths familiar with servicing and repairing them, and the number of remaining factory-trained LE armorers, are seemingly dwindling in numbers, too.
FWIW, the extractor and sear release lever (decocking timing) are fitted parts in 3rd gen guns. Fitting (filing adjustment pad of) the extractor was done by armorers using a factory supplied (sold) extractor Bar Gauge (Go/No-Go). In earlier 3rd gen armorer classes they also used a Flag Gauge, a Go/No-Go gauge to check the dimension between the back of the extractor hook and breech face, but it was dropped and just the Bar Gauge was used. Checking the extractor spring tension was done using a Wagner Force Dial gauge to make sure the tension was within the recommended factory range, and optional extractor springs were available to allow an armorer to adjust the tension to put any particular extractor within the desired tension range. Extractors changed a bit over time, too.
Fortunately, the 3rd gen's, if properly cleaned and lubricated and used with good quality factory ammo, were pretty robust, reliable and durable guns for their time. Especially as design and machining improvements came along. The new(late) production guns were noticeably better in virtually all respects than the early 3rd gen guns.
While I own and use a variety of plastic (M&P's, 99's, Glocks and LCP's), my S&W 3rd gen guns will remain working gear for whatever remaining years of shooting I have left in me.
Well, the 3rd gen's, and my collection of S&W J-frames, of course.
My J-frames are why I originally worked to include a factory armorer course for them, so I could maintain, service and do any needed repairs after I retired. They get a lot of range and carry use, too.