Sig P239 is as long, tall, and wide as is a Glock 19.
And weighs about 3 ounces more, unloaded.
Kahr "P" Series vs. Sig P239 .... "K" series shown, but basically the same as the "P".
If concealment is important.
I'd still rather have the Sig if comfort of shooting factors in. I have shot a couple of Kahr 40's...and the Sig 239 is just more comfortable to me.