Got to use mine in CO last week. Programmed it for my 6.5creedmoor and 7RM, with two different loads for each (Hornady gmx and eld-x in each). Almost perfect out to 500 for all 4. At 700 yds I was off, but didn't have a chrony and was using factory est MV, so not surprising. without actual MV, i didnt try to calibrate. Great RF. Noticeably faster than my Leica 1600, and could go well beyond too. On a bright sunny day, could get rocky/juniper brush mountainside to about 1850 yards. Overcast the next day and I could range same mountainside to 2200 - incredible! What I like most about this tool is it's a small, lightweight device and incredibly long-range, accurate, fast RF and it gives the ballistic solution based on the actual density altitude and temps. Mountain hunters who experience significant changes in altitude and weather during a day will really appreciate the simplicity and small size of this device. Don't have to find the DA/temp/angle and input those into my Applied Ballistics app, this just does it. I didn't use the HUD, but i could see that being very useful on the range. The speed of getting your solution, then dialing, is great for hunters whose targets don't tend to stand still for long.