I have both. I also have the CM9. The CM9 beats both for sheer conceal ability. Sticking to the Shield/CW9 question, it's a wash...both are almost identical in size and weigh the same - in any carry position, both conceal just as well. Now, all of this applies to the Shield only if you're using the 7rd magazine - the 8rd magazine, to me, defeats the whole purpose to the point I sold my 8rd magazine and carry 7rd mags in the shield exclusively.

Each to his own - I carried both. Personally, for a "beat around" gun I choose the Kahr, simply because I don't want to test the limit of my Shields sweat tolerance and durability - I like it too much! The Kahr is cheaper, thus cheaper to replace.

The Kahr has a better trigger out of the box (by a lot) but...well...you decide!