The Viridian has the "ECR" feature. (Enhanced Combat Readiness) It turns off the light and laser when you holster it and turns it on to the last setting when drawn, IF you buy their holster. I found a custom leather maker who supports this system and have ordered a horsehide shoulder rig similar to a Galco Miami Classic. The wait time on that was 12 weeks. Who knows when I'll ever see it given the current state of things. I don't mind the Viridian holster but it's weak on configurations. You can either mount it on your belt or... on your belt. I have one for a Glock that I kluged into a shoulder rig but a kluge is a kluge. I'm looking forward to the custom leather rig. I prefer a shoulder holster for driving. The belt mount is not only uncomfortable in a seat belt but also hard to access.Not big on rails on a handgun but I really like the all black.
The Viridian X5L has been cheap recently. The newer model also has a camera so the gen 2 model is easy to find at half price now. I picked up two from Optics Planet back in November. They come with a coupon so you can order the holster for half price too. (Plus shipping.)