I don't know your specific reasons for wanting this type of range finder, but I can tell you that I wouldn't based on the performance of the RX-III that I have. The RX-IV has a little more advertised reach, and reticle choices but I doubt it performs any better. You won't be frustrated later if you save and spend a little more on a Leica or ( a lot more) Swaro. I sure wish I did.