Always 2nd bowl.
Having a more sensitive scale helps with it updating faster. You can also tap the scale to try and get it to update.
I use a 0.1g/2kg scale for most things, I also have a 1g/5kg one I never use. I can't find it rn but I also have a 0.01g/100g scale for when smartasses on the internet tell me to weigh a 1/8 tsp of pepper.
In my opinion every recipe should be in weight unless there's a good reason to put it in volume. The idea of washing half a dozen individual little measuring cups to prepare one recipe is absurd. Slap a bowl on your scale and go to town.
I didn't, because I felt utterly clueless the whole time and only got the most obvious clues. I felt like the graphical style obscured a lot of the little detailed clues.
The battery life is already not great when running anything intensive. Can't imagine being able to make anymore sacrifices there without making the thing useless.