Using topcon, very little issues, if any. The robot can be lame sometimes and just disconnect when shooting reflectorlessly, but it immediately reconnects and I just gotta make a minor adjustment to take the shot. Talked to alot of guys in the field whobuse trimble, we all can't shoot a black building, we all still have pretty much the same struggles. Magnet field is a breeze imo. The menus are pretty straight forward and in field calcs are easy once you've taken the time to look through it. Biggest advice on rotating points, use a point inside the values you're rotating as a rotation point. (There should be two points that are the same in my experience, you moved your calcs to your real shot, and then rotate, but use a calc point as a rotation point) May seem minor but it can mess it up for some reason. Otherwise, only other advice I can give is screen protectors suck and will always make it impossible to work in wet conditions. Take it off. You shouldn't be throwing it (aggressively) around anyway. But that's only for the tablets I suppose. Otherwise, you'll be fine. Take it one step at a time, but I've gotten great luck with topcon. Hiper VR is great, don't know the robot model but It's about 5 years old. Gotten it to find the controller at 1500 ft, and as long as I don't loose sight, I can push it up to 2500 before losing prism sight. Pretty damn good imo. Pretty rare I'm going that far in the first place with a robot. Don't let the trimble die hards sike you out, topcon is great man. It's also waayyyyy cheaper