I have the X-Sight II and bought what I thought would be a better IR, actually went back to the factory IR which is not too bad at all. I guess if I had big fields and could see 300 yds or more maybe I would want more IR. For me I can shoot to 250 easy with the IR that came with the scope and that is far enough for me. If you are hunting with any high weeds or bush involved, you will need a variable switch to "tone down" the IR to keep from a lot of back wash "white out". If you get the 4K, please do a review on here and share some video. There are many interested folks that would like to see some unbiased real world footage.