See my write up on both the 1600 and 1600-B.
Leica 1600 LRF: actual use?
Both will range to 1975+, pinging off conifer trees or oak brush. Either will give you temp, baro pressure and angle; all useful/needed for your handheld ballistic calc input.
Per the internal ballistic calc, which both have, the 1600 works to 550 yds and the 1600-B works to 875 yds; not a yard further.
For me, the ability to "quickly" range a target "and" get drop data for a target that is 1) within the LRF calc range, and about to disappear over a ridge or into trees is invaluable.
When you ping a target, the temp, baro pressure and angle are ALL computed into the dope given you in the view finder.
My testing, thus far has been VERY promising; both with SHOOTER and EXBAL and actual shooting. I thought it (B model) wouldn't work past 600 yds until I used a 200 yd zero and then it was only 1/4 moa off at 875 yds.
If you feel the 1600 will fit your needs, CamerlandNY has them on sale for $650 vs the previous $800. The B model also runs $800.