I have both and have zero problem with either.
I like the P939 better just because its a 9 and the ammo is cheaper.
Alpha Carry| Sig
P238, P938, P232, 1911 C3 | Colt
Defender, Mustang Pocketlite, 1911 | Rohrbaugh
R9 | Browning
, Buckmark 22LR(suppressed) | Kahr
PM9 Black Rose | S&W
|M&P C.O.R.E RMR Trijicon | Dan Wesson