I’ve been running the XC1 on my Glock 19 since before they were commercially available. I was fortunate enough to get one pre-release as a demo/T&E model, and I immediately put it to work on my gun. Over the past year I’ve evaluated the light during a variety of outdoor and indoor training scenarios. I’ve also run in conjunction with both iron sights and a red dot. Here are some observations that will help the potential buyer.
Attachment: The XC1 is slim, lightweight, and fits snugly to the rail of my Glock 19. Once it’s mounted, it feels secure and doesn’t move. The only thing I don’t like about attaching it is the feeling of the tension screw. Compared to my X300 A&B models, the attachment seems less robust. Still, it’s never come off or even loosened during regular use, and there aren’t many ways of attaching the light while retaining the minimal profile. As long as you’re careful not to over-tighten the screw, the light should mount quickly and securely. Over-tightening may strip the screw, which will require repair.
Activation: I shoot with a thumbs forward grip on the gun. With my support hand thumb parallel to the slide, momentary activation is easily accomplished by pushing the toggle switch down. I really like this for structure and area clearing where light discipline is important. However, reaching the switch for constant on is impossible without moving my support hand grip from the gun. The constant-on switch is placed more than an inch ahead of the momentary on switch, and is only accessible from the left hand side of the light. Turning off the constant on function was equally difficult, as the switch must be pushed back from the right side of the gun to the left, which requires me to reach my support hand under the frame. There is currently no pressure-sensor option for this light, so you’ll be manually activating the controls whenever you use it.
Illumination: Interior spaces are where this light does great work. It has a diffused white LED that puts out a wide spill. When you have walls and interior spaces for the light to bounce around, you’ll get the most of out what you’re working with. However, once you get out past about 15-20 yards, you’re going to run out of light fast. Depending on your carry setup and which set of statistics you believe, this should be adequate for most concealed carry applications where you’re worried about an attack in personal or intimate space range. For most people, a light that will reach two or three parking spaces away in a dark parking lot or down the hallway or stairwell will be adequate. If you want something brighter, you’re going to need to go up in size to a larger light, which will overhang the barrel. That will increase the overall length and affect holster and concealment options. At that point, you may as well carry a larger gun like the Glock 17 or 34.
Battery Life: When the battery compartment cap is properly installed, battery life is fair. When I first got the light, I tended to over-tighten the cap. Because of that, I had a passive battery drain that killed the charge within 12 hours, even though the light was at rest in a holster. This persisted until I purposely began tracking the battery drain I was experiencing, and began backing the cap off. The last battery I installed was on 11/3/2016, and I used that light on and off until it was changed on 12/22/2016. While the battery life is not going to be nearly as good as a light with larger cell batteries, using quality lithium batteries seems to get more usable time. As a best practice, a function check of the light should be made prior to leaving the house if this is in your EDC rotation.
Use in Conjunction with Sight Systems: I’ve run this on two different 19’s. One is my G4 MOS with an installed 3.5 MOA Trijicon RMR. The other is my completely practical G4 with Ameriglo Spartan Tacticals. Indoors, I’ve found that the light works well enough to use in conjunction with both the red dot and the iron sights without consideration. There’s enough spill to see my front and rear sight notches, as well as the dot. Outdoors, I’ve found that the dot of the RMR is generally too bright to use very effectively out past 15-20 yards. At that point, unless you have a self-adjusting optic or have remembered to turn the dot intensity down, the dot will be too bright in the reticle to allow you to see the targets. This was not an issue with brighter lights such as the X300 Ultra. Again, if you’re planning on clearing open spaces, this isn’t the light you want. If you’re not using it professionally, however, the light is pretty fair when it comes to concealed carry applications.
Overall, I think that the XC1 works well in conjunction with a mid-size concealed carry firearm. The light is minimal in size and weight, casts good illumination in close distance shooting, and takes batteries that you can find at Wal-Mart at 4:00 AM. The only negative to the light is the battery life issue, which is mostly eliminated by using good lithium batteries, checking your gear each time you leave the house, and not gorilla-fisting the battery screw into place. As with any WML, a hand-held backup light is always a must. A regular battery rotation schedule based on user observations is also advisable.