I liked my Mustang cocked and locked in my Ahern Pocket Natural in my youth. Luckily, I got older and wiser quickly and upgraded to a S&W 3913.
I think the 938 would be a great 2 O'clock IWB lighter carry option when an Officers Model is just a bit too heavy. (summer shorts). I'm sure they will keep it thin.
I'll comment again that I've never owned a Sig, but do admire them for putting night sights as standard on many, many, many of their pistols.
Bud's is running a deal on the 290 right now with NS and laser. If it was 6 oz lighter and the mags $10 cheaper, I might have bought one.