I love multi-emitter lights, having a small collection of examples from wurkkos, convoy, lumintop, and I have more on the way from other brands as well. But this light really deserves a special place in my collection due to the combination of features that it offers, and more importantly the driver that's found in the light.
Build quality is top notch, everything functions as it should and I'm amazed at the wealth of additional accessories that comes by default, allowing you to customize the beam profile as you see fit. A bonus for me as the additional optics is actually compatible with some of my other multi-emitter lights too! The only drawback that I noticed is the loose magnet in the tail, which gives an audible click when you attempt to stick the light to a surface, but it looks to be easily fixable by adding some double sided tape to prevent movement.
Of the two X4 examples I have, this is configured with a FFL351A 5000k, and compared to the FFL707A 5000k in the X1S Pharos, the latter gives a tight hotspot that is good for medium distance throw outdoors, while the former has a much larger beam that makes it very versatile for everyday use. The driver is amazing in performance, sustaining the highest ramp (not turbo) for 20 minutes without a noticeable drop in brightness. It does get very hot (with the head being painful to the touch), but it's also a sign that the driver has excellent thermal management and performance, certainly the best performer by far in my collection.
Lastly, the lantern attachment, it's a pretty novel feature and performs extremely well given how low of a brightness level the X4 is able to reach, although for my personal use in lantern specific scenarios, I'd likely still reach for my LT1S. If this is your only light, having the attachment just makes it that much more versatile for multiple scenarios. I personally find this paired with the X1S Pharos to be a great everyday carry combination (assuming you have the space). If you're looking for the perfect EDC light, this is the bar to beat!