Well, I bought the first one to show up in in my favorite gun store.
Barrel is fluted with a slight taper to the front of the underlug. Looks nice and may even facilitate easier holstering to a degree.
Front and rear sights dovetailed for conventional sights. Mine (night sights) are zeroed very well. The three dot system is easy to acquire---quickly. The dots on the rear sight are close together, of course, since the sight width is narrow in order to fit the narrow width of the dovetail. Any sight adjustment would cause the sight to overhang.
As stated, my sights are on the money, or close enough with a variety of loads.
The front sight is on a high ramp that is dovetailed, and the inserted sight sits even higher. Noticeably higher than any standard 640 sight and even higher than with the Express Standard Dot. Gun still fits the 640-1 holsters I stuck it in.
Trigger pull was a little over 11lb.---and SMOOTH. Though there is some stacking at the front of the pull, as is common with 640's. Just pull straight thru and you won't notice.
Truth is, gun is fine right out of the box.
Of course, that didn't stop me from fiddling around with it. I replaced the rebound spring with a #14 lb. I smoothed the rub marks on the hammer with an Arkansas stone. Also the bottom of the rebound slide. Trigger pull was reduced to 10lb. 14 oz. Probably more because of the lighter rebound spring. Gun was dry internally--no lube. I used a thin coat of TW25B on the trigger pin and a little on the side of the hammer. And under the rebound slide. Not much.
Tried a lighter spring when I shot today (trigger pull 10lb). Everything went bang, but some primer dents were very light. Back in went the original hammer spring where it's going to stay.
Didn't like the looks of the S&W grips, but have to admit they shot OK with standard loads.
The gun now has Packie Decelerators, since my carry load may well be reduced power .357 DPX, that still drives a 125 gr. bullet at 1260 fps from the 2 1/8th" bbl. For comparison, the same DPX is 1325 from my M66 3", but it is tight and produces velocities higher than my 4" 586. Used Pro Digital chrono from Competion Electronics.
Recoil was managable with the .357 DPX using Hogue soft monogrips. Today, +P 125 gr. was no problem at all with the new Decelerators.
No doubt, some young whippersnappers can shoot full power .357's without issue. Those were the days.
Didn't do much in the way of an accuracy test, unless you count dinging away on my Evil Roy Portable Steel Targets. Out to 15 yds where the sights really come in handy. At closer tanges the sights are also worth their weight in gold.
The cylinder is recessed for moon clips, with an outer rim on which about 25% of the case headspaces. Whether you use the moon clips or not. Primer dents were just fine, moon clips or without. Apparently, the moon clips are just used as speed loaders, which offer positive ejection---especially with the longer .357's. All the cases are coming out together without any hanging up. Three moonclips are included.
I haven't used the clips before. These are thin (.024) and fit just below the rim so, as mentioned, the case heads rests on this rim. I bent one before I figured out how to insert them. A little twist as they go in and out and no problem.
I think the clips are the best way to go when you load up. Don't know if I'll give up my HKS speedloaders for reloads, however.
Hope the above was helpful.