This is one of those perennial questions that come around, comparing the versatility and practical value of a 5-shot snub (be it .38 Spl or .357 MAG), versus the 7 or 8-shot 9mm. Not a bad question, and often one that's enjoyable to discuss.
I own several S&W 5-shot snubs, 2 of which are chambered in .357 (a pair of M&P 340's).
I own a pair of S&W 3913's, 1 regular and 1 late production 3913TSW, as well as a CS9 (3" & 7-rd mags). While I went through a buying flurry of smallish 9's & .45's at the end of the 90's (and later some smallish .40's), using them all for quals, training & practice, in my role as a LE firearms instructor, I eventually returned to carrying one of my assorted 5-shot J's on my own time. They were easier to carry (especially pocket-holstered), and I didn't consider their 5-shot capacity to be too much of a detriment in the anticipated role for which I carried them (meaning potentially against 1 attacker, maybe 2).
Once I retired, although I remained active as a LE firearms trainer & armorer (and a reserve), I found myself carrying my 5-shot snubs even more frequently. My 7, 8 & 10-shot 9's (CS9, pair of 3913's, G26's and a SW999c) saw a lot of range time, but less carry time. My pair of 642-1's & M&P 340's saw a lot more range time
and a lot more carry time.
So, depending on my manner of dress and planned activities ... and
where I plan to engage in those activities ... I'm much more likely to be carrying one of my J's instead of my little 9's (.40's or .45's).
However, nowadays I'm even more likely to be carrying one of my pair of LCP .380's, discreetly pocket-holstered, when my choice of jeans have pockets which won't conceal one of my snubs.
Yes, loading (same thing as "reloading"
) is usually faster and simpler when using a pistol, than a revolver, for most people. That doesn't a revolver can't be loaded quickly or deftly, though, which is where some long time revolver users may benefit. Also, speedloaders are typically faster to use than speedstrips (although some experienced revolver hands may be able to use one of the older "spaced pairings" leather ammo carriers almost as effectively as speedstrips).
In keeping with the old saying of TANSTAAFL, there are always going to be advantages and disadvantages to consider, and some conditions and individual needs may favor one type of smallish defensive weapon over another, especially for different skill levels of users.
I'd never willingly wish to get rid of my CS9, 3913 or 3913TSW, but neither would I wish to get rid of my 5-shot S&W J's. They all serve my needs admirably, and I've invested a number of years running them on the LE range.
The only reason I don't own either a Shield 9 or a G43 is because I have my other single stack S&W's (and a pair of G26's and a SW999c), but if didn't own them, I'd probably own both a Shield and a G43.
I'd be running both through all the normal quals, training drills and regular practice at every opportunity, too.
Matter of fact, I'm thinking about going to see the new Aliens franchise movie in a little while. I think I'll take whichever one of my M&P 340's is in the lockbox close at hand (versus in the safe). Nicely prominent front night sight (XS standard dot).
Ammunition?
Typically my 9's have been loaded with some different 147gr loads (incl Rem GS and W-W T-Series), 124gr +P GS or T-Series, or the earlier issued 127gr +P+ T-Series.
My .38's are usually used with Speer 135gr +P GDHP/SB, Rem 125gr +P GS or W-W 130gr +P RA38B (same as PDX1). While I've used some assorted .357 Magnum in my M&P 340's (for some quals, check different brands/bullet weights for bullet pull, and just to demonstrate I can run the little guns with the hard recoiling Mag loads), I typically train & qual with, and carry, .38 Spl +P loads. Even faster when it comes to sustained controllability and recoil management during rapid shot strings. Less brutal on the hands for range sessions, too.
So ... little single stack 9 or 5-shot .38/.357?
Sure. Whichever, for whatever reasons seem practical and relevant to the individual.
I plan to keep owning and using both, myself.