While I briefly owned a 469 ("2nd gen") in the late 80's, it wasn't until I was issued one of the early production 5903's that I started to pay a lot of attention to the S&W autoloaders.
I've carried one or another issued 3rd gen model since '90. They've included 5903, 6906, 4013TSW, 4566TSW, 4513TSW & 3913TSW models. When it comes to personally-owned models, I have an 'original' 4513TSW (cutaway grip, 6-rd mags), 3913, CS9, CS45, 4040PD, 4013TSW and a new production 3913TSW.
I've also served as an armorer for the 3rd gen pistols, and have been through the armorer class 4 times.
While I grudgingly carried my first issued 5903 (I traded that earlier 469 off because I didn't care for it), I quickly came to appreciate the rugged reliability of the 3rd gen guns in LE use. They ran, and ran well, with any good quality factory ammo I cared to try, or saw used, over the course of the last 25 years.
Sunshine or freezing wind/rain, they ran ... as long as the users bothered to clean and lube them now and again, and didn't expose the firing pins or extractors to excessive amounts of solvents, CLP's, lubes or greases.
Our supply of spare/repair parts was pretty meager when I joined the armorer staff, but it wasn't often needed in order to keep our 450+ guns up and running. More shooter-induced issues than actual gun issues. After those early 3rd gen's had been in-service for going on 16-20 years, they were replaced with new production TSW's (in 3 calibers). Those gave decent service for several years, until it was decided to transition back to allowing personally-owned weapons (first 3, now 4, approved brands) and new issued plastic guns (M&P's, in 3 calibers). Time marches on.
On the plus side, the M&P's seem to run fine whether dry or lubed, and it's a simpler design to clean (at the user level), as well as maintain and repair, than the 3rd gen's (or some other major brands of metal-framed pistols). No fitting of parts. (The 3rd gen's require fitting of the extractors and sear release levers, which means some gauges nowadays, and an occasional barrel may require some minor fitting of the barrel tab.)
Armorers can be trained faster. Even fewer spare/repair parts will likely be needed, if the M&P's that have been used for T&E, and owned by various range instructors going back to '08, are any indication.
I'll always enjoy the 3rd gen's I've acquired over the years, and consider them to be excellent quality service-type pistols.
Personally, I considered the newest production TSW's ... meaning about the time they were dropped from the commercial catalog and were only occasionally produced for LE orders from existing S&W agency customers ... to be capable of being compared to any of the SIG Classic Series TDA pistols in both reliability, practical accuracy and overall functioning. (I've been trained as a SIG Classic series pistol armorer, too, and have handled/fired my fair share of SIG's, starting from when they were first imported as BDA's, up to the latest of them.)
S&W never seemed to be overly interested in 'dolling up' their 3rd gen's, nor make them finely finished and pretty ... but they worked.
Just my experience and thoughts.
Seven DAO S&W's ! 
