Eazyeach said:
Also the SIG doesn't have the awful magazine disconnect safety. I won't own a weapon with that.
It's relatively easy to remove for someone with very basic gunsmithing skills, so I wouldn't let that be the sole critical factor.
Both guns have ergonomic quirks some don't like: the slide-mounted decocker/safety levers on the Smith, and the thumb-decocking lever and resultant rearward-mounted slide stop on the SIG. The decocker/safety levers on the Smith are awkward to reach (less of a problem if you don't actually use them as safeties), and they get in the way during rapid slide manipulation. OTOH the controls on the SIG can be awkward for lefties, and some people have problems with riding the slide stop, which can cause the slide to fail to lock back. That said, I'd say that the advantage goes to the SIG, as the controls are less obtrusive. YMMV.
The SIG is easier to field-strip because the slide stop doesn't have to be removed (and potentially lost), the frame and slide don't have to be precisely lined up against recoil spring pressure to remove and reinsert the slide stop, and it lacks the fiddly little frame levers that have to be pushed down on the Smith. That said, IMHO the Smith is not genuinely difficult to field-strip.
FWIW the Model 5906 is a significantly heavier pistol than the P226 because the M5906 frame is stainless steel rather than aluminum alloy. The alloy-frame Model 5903 is a closer match.
On a similar topic, the M5906 was offered in a "Me-Too" thumb-decocker version: the Model 5926. However, this pistol isn't nearly as common as the M5906, although prices seem to be very close in less-than-LNIB condition. (S&W collectors are like Colt collectors and will pay top dollar for LNIB examples of rare models even if those models were not well-liked; of course, they're often rare BECAUSE they weren't well-liked.
)
A thumb-decocker alloy-frame Smith would have been the closest possible match, and this pistol would have been called the Model 5923, but AFAIK this is one of the 3rd-gen Smith model combinations that is believed not to have been produced.