In the next beta, we will have active by default a new tool to design with control. Real-time weight for metals and gems inside all 2Shapes commands.
As you can see, you can see the weight (and the gems and gems weight if exist). Any change you do even inside the command, you will see in real-time.
You can enable/disable it from Settings > 2Shapes.
If you have any questions, please let me know.