A bit late to the party but here's my take on 9mm revolvers:
1) The main advantage of a 9mm revolver over a .38 Special revolver is the ability to use moon clips with a short cartridge that aligns and loads very easily with the chambers. If I the bullets have a round nose profile or anything close to it they almost guide themselves into the chambers.
2) Moon clips are cheap compared to a speed loader and take up less space. You need to avoid the cheap mild steel clips, but well made clips like those sold by TK Customs (which appear to be OEM for the Ruger 9mm revolvers) work very well.
3) Moon clips allow for a faster reload, on the order of about 1/2 second less than most speed loaders.
4) Moon clips also provide for more reliable ejection with zero chance of a cartridge getting stuck under an ejector star, a failure that will prevent a reload and require several second and some fine motor skills to clear.
5) In terms of power, a 9mm will give you .38 +P velocities at comparable bullet weights, albeit at higher pressures with a bit more muzzle blast.
6) The downside of course is you are limited to 5, 6 or 7 rounds in practical concealed carry sized 9mm revolvers.
But let's keep that in perspective. Data on defensive handgun use is controversial as in the vast majority of defensive handgun uses, the event is not likely to be reported. Defensive handgun uses occur on various levels.
A) Most often, an individual conceal carrying a handgun who demonstrates a reasonable degree of situational awareness also won't be displaying the tells a potential assailant is normally expecting to see. They will quite often note the assailant and make eye contact making it clear there is no element of surprise. A professional / competent criminal might not key on exactly what's wrong with the picture, but they will seek a softer target. In that case the would be victim avoids an assault or robbery but never knows for sure that a crime was prevented.
B) In a smaller number and percentage of defensive handgun uses, the would be victim may begin to draw or actually draw the weapon. Again, a competent criminal will recognize they are about to be shot and discontinue the assault. In those case, most people would probably not report the occurrence to law enforcement, especially in urban settings where police departments are often not very supportive of armed citizens and concealed carry permits.
C) The next level is the would be victim actually firing the handgun, without hitting the assailant, who again discontinues the assault and flees. This is more likely to be reported, especially if there were witnesses and almost certainly reported if the victim was injured in the assault.
D) The level where defensive handgun uses begin to be reliably and consistently captured in the data is when the victim actually shoots the assailant. That might be 10% of total handgun uses.
Of those assailants who are shot, the data suggests that about half of them will immediately flee or surrender as they don't want to get shot again. The cartridge used makes virtually no difference, as long as the assailant knows they've been shot, the potential for a psychological stop is in play.
E) In that half of defensive handgun uses where the assailant is actually shot, and doesn't immediately stop, the cartridge finally starts to matter. That's maybe 2 1/2% of all defensive handgun uses.
F) In the those cases where multiple shots are fired, the gun fight is still over in 5 rounds or less in 5 seconds or less, at 5 yards or less, around 90% of the time. That 10% where more than 5 rounds is required is one quarter of one percent of defensive handgun uses - 1 in every 400 defensive handgun uses.
In my case, I had two work related defense handgun uses and in both cases the assailant stopped as soon as the duty pistol was drawn. I also had one attempted mugging where I drove the assailant back with a strike to the chest and driving into him to block the knife and keep him off balance while blading my body and lifting my jacket to draw my concealed handgun. I never got the chance to complete the draw a she immediately fled as soon as he realized he was about to get shot.
It won't be popular, but the fact is that armed citizens are not chasing bad buys into dark and scary places. In fact, they should be using a reasonable level of situational awareness to detect and then retreat from or avoid a high threat environment.
If you want to carry a bat belt with a full size duty 15-17 round duty pistol and two spare magazines thinking you might someday need 46 to 52 rounds of ammunition, knock yourself out. But the odds are you'd only need more than 5 rounds in just 1 out of 400 defensive handgun uses - and the odds are if you ever do need to employ a handgun in self defense, you won't even fire it.
——
9mm revolver wise, I have, in increasing size, a Taurus 905, a Ruger SP101, a Ruger Speed Six, and an RIA imported Alpha Proj AL 9.0.
The Taurus 905 is a variant on the Rossi/Taurus 85, which in turn is basically a S&W Model 36, introduced back when S&W owned Rossi. Like a J frame Model 36, it's a compact five shot revolver well suited to concealed carry. Taurus quality is however…spotty…at best. I bought this one at a local gun shop and bright it back less a than an hour later when I discovered the cylinder would not close into the frame with a loaded moon clip, as the cylinder was not properly cut for the rather thick moon clips that came with it.
The shop gave me the option of sending it back to the factory for me, or giving me a refund. I took the refund, but four months later when it came back from the factory I purchased it again. The DA trigger pull is quite good, but it's also primer sensitive as it won't give 100 percent reliability with CCI primers. With Federal and Winchester primers, it's been 100%.
The Ruger SP101 is my most recent acquisition and my experience with the SP101 has been checkered. I have had a 3" SP101 in .357 Mag for over a decade and it's been an excellent revolver. I did install a lighter trigger return spring and lighter hammer spring to reduce the DA trigger pull weight. I also bought a 4.2" SP101 that had an improperly cut forcing cone. Long story short, two trips back to Ruger, out $75 in shipping when they lost the receipt, and then a replacement revolver about 5 months later than I expected as then didn't bother to tell me they would not ship it until they made another run of them.
I probably would not have bought this last one, except I really wanted one in 9mm, and it had been years since I'd actually seen one in a local gun shop (local in this case being about 90 minutes away). The first one I tried felt exceptionally gritty, but the second was fine and after a close inspection I bought it. I should have inspected the accessories as I discovered it did not in fact have the expected envelope with three moon clips in it.
But kudos to Ruger as I sent them an e-mail after on Saturday and they called me back by 10am EST Monday morning, and overnighted moon clips to me.
My Ruger Speed Six in 9mm was acquired used and like my other Speed Six in .357 Mag and my 2 3/4" Security Six in .357 Mag it's a superb revolver, if a bit large for a 9mm revolver.
My Alpha Proj 9.0 is K frame sized and is a decent range gun. However, the chambers needed polishing before it would eject cartridges smoothly.
Of the four, the Taurus 905 and SP101 are best suited to defensive concealed carry purposes. As always, the peg grip frame on the SP101 makes it extremely accommodating for after market grips to adjust the revolver to your hand size and there is a huge number of available grip options out there. The selection and range of adjustment via grip for the Taurus is still good, but more limited than the SP101.
IMG_20201209_145418094
. Hunting, Self Defense, target shooting, plinking ... what else is there? 
