+P .38spl vs a full house .357magnum....
In my opine, a .38spl +P or +P+ round works best in small frame(J frame size) over a full power .357magnum.
.357magnums are tops for LE & armed citizens but meant for K/L/N frames or the robust GP-100 series. Barrels: 4-6".
I'd pack a few .357magnum 125gr JHP or maybe a top load from DPX, Speer Gold Dot, Federal, Buffalo Bore, Golden Saber but only in a speed strip or 2.
If a critical incident has gone sideways and I'm in dire need of a spare strip, I'd either flee or load up a snub with magnum ammunition.
Clyde