I have a Kahr MK9 which is the all steel (stainless) subcompact. It's quite the shooter and is quite concealable.
The only downside of this gun is the weight (considering the small size) so you're not going to pocket carry this one.
Kahr's are rather expensive...
However, there are a number of subcompact 9 mm's available (Taurus comes to mind). I suggest you consider how you're planning to carry (in your pocket? Inside the waistband? outside the waistband? You'll want a nice quality holster any any method of carry.
I've carried for more then 20 years. My carry guns are as follows:
1) Taurus 85 Multi-Alloy: .38 Spl, 5 rounds, Aluminum/Titanium, weight (unloaded) 13.5 oz. I normally carry this in a pocket. This is my most frequently carried gun due to weight, size and the ease of pocket carry. This one goes everywhere I go.
2) Glock 19: 9 mm, 15 rounds, polymer/steel, weight (unloaded) 21 oz. I carry this one outside the waist band. you will have to wear a covering garment of some sort. This Glock fits my hand the best of any of my handguns (got 9 or 10 all told)
3) Kahr MK 9: 9 mm, 6 rounds, stainless steel, weight 21 oz. I carry this one outside the waistband. A tee shirt easily covers this one
The Glock and Kahr are carried frequently (not both at once). It took me a long time to find a holster I liked for the Kahr. Since I've found a holster I like (and have it broken in now), the Kahr is my second most frequently carried gun. As far as round count for the Glock and Kahr, I quoted the magazine capacity. If you carry with one in the chamber, add one to each count.
Good luck in your selection!