I'm sorry, did someone call for the resident Grand Power pimp?
The STI GP6 is the gun I currently shoot. I had the older first generation K100 before this one.
Since I admit to being biased, let me start with the downside.
The STI badged guns had some problems. The STI pattern hammers had a reputation for breaking. The Grand Power style hammers seem to be better. My guess is the STI style hammers were MIM'd instead of machined. I have pictures of one slide that had cracked, likely after two seperate ruptured cases due to poor reloaded ammo. I know of another broken slide but have not heard how/why or seen pictures. I know of at least one gun that was shipped with a bad extractor.
And before you start thinking the guns are crap, the lines above could have been written about Glock/Sig, etc. They have all shipped guns that later had failures. The big question is what they then did about the problem.
As far as I know, the current generation of Grand Power guns have addressed any weaknesses found in the older generations.
My current STI GP6 has about 8-10 k through it. I haven't had anything go wrong with it yet. I just replaced the hammer group. I got the new X-Calibur hammer group for it so it will feel more like the new gun when it arrives. The old hammer only shows a little blueing wear.
The biggest selling point for the STI GP6 or K100 for me has been the trigger. It's nothing short of awesome. It's got to be tried to be believed.
The next selling point has to be the recoil feel. The rotary lock-up seems to take a huge amount of the snap out of the recoil. The muzzle climb seems flat.
The older Mk6 frames fit most peoples hands. The newer Mk7 has the interchangeable backstraps so you can switch to better suit your grip.
If you have the chance to try one, see if you can shoot it back to back with the CZ 75/85/SP01. I think you will enjoy the comparison.
At last look, Freedom Ventures still have some of the GP6's in stock.
Next month (or so?) Blueline will be getting thier first Grand Power shipment.
Included in the Blueline order is the new X-Calibur model. It's like the GP6C or K100 Target with 20 mm more barrel and a slide to match. It also has a new trigger system that is even lighter than the already awesome K100.