I respect the quality of the products from manufacturers like Streamlight, Surefire, Elzetta, and Malkoff, but like the discussion of the battery types shows, there are trade-offs. The main issue with them is that these brands make products for law enforcement and military in mind hence their designs, outputs, and purpose is really for those clients rather than a general user. They often focus on durability and simple modes for reliability and predictable output. That's great for a LEO and military user, but for a general user or even an outdoor user, it's far from practical and in fact, detrimental. Many products of these US-made, tactically-mind products only have two modes, if that. Not exactly great for flexibility and optimizing run times vs. output. Also, like the latest posts show, makers often prioritize the use of primaries for reliability over rechargeable lithium ions. I get why, as primary lithiums have a long shelf life, are less sensitive to extreme temperatures, and less prone to failures from battery chemistry. This makes them better for use in mission-critical situations or where you simply just need it to work on the first try. However, always using primaries on a power-hungry tactical flashlight isn't economical. As a guy who often went camping with a SL Scorpion and a Surefire 6P two decades ago, I loved their intense output, but didn't like how their single modes drained the expensive batteries. I ended up only using them when I really had to. Now, a lot of the Chinese brands offer flexibility with multiple outputs and modes, so the user, not the maker, has more control over the product and its use. I appreciate this approach given I really don't use a flashlight for tactical purposes.
Simply put, I think US-made brands like Elzetta, Surefire, and the like make excellent products but really only for the tactical user. For a weapon-mounted light, these are the best ones to get given the durability, reliability, and simple output modes. However, for general use or even outdoor recreation, I find brands like Fenix, Klarus, Nitecore, etc. to make much better overall products given all the options you have with them ranging from outputs, modes, to battery types.
I'd like to buy an Elzetta or Malkoff one day, but for me to justify that, I'd need a few of my other flashlights to fail and break first.