Just to clarify the OP's original question. I believe he was asking for info on the 1600 arc rangefinder not the Bushnell fusion 1600 which is the binocular/rangefinder combo.
FWIW, I have read on other chat forums that the 1600 arc is very similar to the older 1500 units but with better rubber armour, updated ballistic technology and an upgrade in glass with rainguard.
I have used Bushnell rangefinders for years and have never had an issue with any. They are as good as it gets in their price range IMO especially if you buy the upper end like the 1500, 1600 1200, 1000. I wouldn't hesitate to buy it and use it hard in the field.
The specs can be seen here.
Bushnell - Elite 1600 ARC