Well, I had no problems ranging deer out to over 1000 yds with my LRB 7x50's last season. They worked perfectly. About my only complaint with them is they're a bit big and heavy. But I'm happy enough with the performance I might give the new 7x40's a try--they look like they'd be much nicer to carry.
Of course, it's important to note I'm on my 3rd one. The first two were junk. I sent them back and they were replaced under warrantee for free. The one I have now flat out works.
Those range finders are made in the Soviet Union. I bought two different name types. one like the one you are talking about and an ospery. They are supposed to be able to range up to 1,500 yards and show speeds up to 999 mhp. I had two of them in my hands and they would only range about 260 yards. It would not even range a house down the street at 300 yards. I sent both back to the two different dealers and had them also try them and they emailed me back and said I was right. They are junk. The price is good but they will not even range a cow or horse at 250 yards or a damned house at 300 yards.