First, let me say that a 5.56 AR is a far more effective defensive tool than a 9mm carbine. With that out of the way, the only PCC I have any real interest in is the Cx4 Storm. They're pricey at MSRP, but I got my current one (third total) a year ago for right around $600.
Short, light, accurate, reliable, comfortable to shoot, easy to customize. The stock trigger isn't great, but it works, and can easily be upgraded with Sierra Papa fire control parts. Mags are plentiful and fairly inexpensive, with Mec-Gar 20 rounders being my favorite, though Beretta has 30 round mags too. Also very quiet suppressed with 147gr. Gold Dots.
good to hear from you. I'm glad that you are happy with your choice of the storm for a PCC. Lets face it, if we all liked the same weapons we would not have nearly the variety we enjoy these days! I actualy looked at the storms back when they first came out. At the time they were available in 9mm and .40S&W. In general I did not like the feel of the storm with it's short butt stock and scratchy trigger and I was not happy with the 9 or 40 as A carbine round. Both are lacking in terms of powder capacity and therefore velocity. In general I wanted something with more power and the ability to reach out farther. Since I had a glock 20 barreled for 9x25 it made since to me to match my PCC to that pistol. This way I ended up with a more versatile weapon that's good for short range and can reach out a little also.
As for the 5.56, let me say I would rather have the 9x25 at close range. The 5,56 is a great round and I have several but they are known for having pass throughs were the bullet does little more than create a 22 caliber hole through the target. This is something the military has experienced time and again and even with the re-design of bullets has not been able to overcome. The 9mm, taveling at speeds the 9x25 is capable of is going to expand in the same way the .357 magnum always has. Again, each to his own.