Well, I own both the CS9 & the CS45 ...
I use the CS45 with Big Dot sights, and it's more than acceptable for reasonable defensive ranges. Using the stock factory 3-dot sights this pistol can turn in some very surprising accuracy. This small 3.25" barreled .45 pistol can be a handful, though, and I find the slightly larger 4513TSW, or 457, to be a more comfortable .45 pistol to shoot for extended range sessions, even with +P loads. Also, like some other subcompact .45's, this pistol requires a firm grip for proper functioning.
The CS45 had some minor issues with some of the early magazines that were resolved, and a few of the early pistols escaped the factory with barrel tab tolerances that were a little too tight. Mine was one of them, but after correcting the tolerance and using the current magazines it's been fine.
One of our guys "retired" his Colt Defender in favor of a CS45 for off duty carry, and he's been quite happy with it the last couple of years.
The CS9, though ... now that little pistol is simply fun to shoot. It balances and handles even better than my 3913, and I never thought that could happen. I held off ordering a CS9 for quite a while, satisfied with my 6906 & 3913, but the more I shot one of the other staff's CS9's ... the more I liked it.
Even with the wider notched Novak Ghost Ring rear sight I installed it's a very accurate little pistol. It'll easily equal the acuracy of my 3913.
The thing, though, is to see whether the factory supplied Hogue grips fit YOUR hand as well as they do mine. If they don't, you may as well look at other pistols, as there just aren't any other choices at this time. S&W uses the short & fat Hogues to help dampen the recoil of these little pistols.
If I could only have one of these pistols it would be the CS9, hands down. It's small, light, balances well, and is more than accurate enough for any reasonable defensive use ... and even some unreasonable "precision" shooting ...
I've fired a little less than 1,000 rounds through mine so far ... a mix of standard pressure 115gr & 147gr JHP's, some 124gr +P JHP, and some 115gr & 127gr +P+ JHP's. Nothing but complete reliability from the first round fired ... Of course, that's the way it was with my 3913, too ...
I find the size and feel of the CS9 to be perfect for my hand.
Oh yeah, like Mac said ... the "traditional double action" means that the first shot is DA and the following shots are SA ... and the hammers are the standard spurless design used on the other S&W compacts ...
You should rent one of each, if possible, and shoot them for 50-100 rounds for yourself ... Check out the S&W Forum and search in the Semiauto Pistol forum using CS45 & CS9 as keywords ...
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