Mine is now back, well a replacement unit at any rate. In my somewhat chilly office a fresh battery has just lasted 2hrs 12mins. It still has 1bar left, but for all intents and purposes I'm calling it flat at this stage as the rangefinder packs in at 1bar.
That was with the screen on all the time and a fair bit of playing about with it at the back door, messing with the rangefider and going through menus etc.
Do I mind swapping batteries every 2hrs? Not sure yet… I'd rather not, but it's not a massive chore if you get your pockets organised and you know a change is going to be needed at least once a night.
It is a lovely bit of kit, honestly it is, but they have shot themselves in the foot by not doubling up on the battery compartment and giving it twice the life.
The unit finally shut down after 3hrs 46mins, so that's 2:12 with rangefinder capability followed by 51mins on one bar and 43mins with no bars at all and a critical red battery symbol.
I think their intention is "probably" that the laser carries on working until all the bars vanish, but something is clearly wrong with the battery levels as it carried on with no bars for an astounding 43mins. Whether a future firmware upgrade can fix this and give more laser life, I do not know. I am undecided what to do to be honest. It's a lot of money for something that doesn't live up to expectations. If the laser worked until that last bar vanished I would have no complaints at all.