I carry a G27 off-duty, and have been carrying it for about 6 years now. It's been a great gun. I have it set up with Trijicon night sights, as well as the Pearce +1 grip extensions for 10rds in the mag. These are necessities for a CCW gun. This gives me 10+1, as I always carry a round chambered and am vehemently against "Israeli carry".
I actually shoot my G27 a lot at the range. I also shoot IPSC league on Mondays, and I occasionally will leave the G34 in the car and use my G27 instead. The last time I used my G27, I won the Production class and took 3rd overall for the night. It was shorter range courses of fire that night. If I see that we're going to be doing some longer shots (20yds+), I do go back to the G34. It is a very remarkable gun once you learn to shoot it. I shoot 100% with it on every annual qualification (mandated per dept policy) without issue. I used to be the only one with a G27 for off-duty. Now about 6 guys have them.
I've said it in a previous thread, but the G26/27 pistols are truly combat-capable. Most CCW pistols are designed for a quick response defense situation, whereas the G26/27 has a capability of being an offensive weapon in the event it must be used in a drawn-out incident, such as an active-shooter scenario at a school or shopping mall. I also used to carry a Kahr PM9, and it was a very easy gun to carry off-duty. It was also very accurate and I liked it. However, a 6rd magazine and the shorter, smaller design of the weapon made it a purely defensive weapon. For a typical carry scenario, that's all you need. For me, I decided that I wanted a weapon that would allow me to engage multiple threats in an offensive, as well as defensive, capacity. My agency's policy has language in it that basically says that if I encounter a violent felony crime (aggravated assault, robbery, kidnapping, sexual assault, etc.), I'm doing it under the auspices of a police officer, and as such I have the same duties and liabilities associated with it as I would on-duty. Basically, that means that there is an assumption that if a major critical incident arises, I am obligated to get involved if I am carrying. Because of that, and the fact that I do believe in the merit of that policy, I decided that I needed to bring the proper gun to the fight.
I will say that the G26 is a suitable alternative, and there are two advantages that it has over the 27. First, you have an additional round in the magazine, so when you get your grip extension, you can go 11+1. Second, the recoil is less, and with the smaller size of the weapon, you will have more control. I have been able to shoot my 27 very well, but it wasn't until I started lifting weights regularly and really developed my grip and arm strength that I really became exceptional with the gun. The smaller size and added recoil of the .40 make grip strength a very important variable. Just something to think about.
The S&W M&P40c is also a viable alternative, and I wouldn't rule them out until you try them. They're $455 with night sights, so right on par with Glock.
If you do want a Kahr but want to spend less money, look into the CM9. It's the same as the PM9, but they used some different production process to make it about $200 cheaper than the PM9. LEO price is $360, and PM9 price is $540.