At first sight, if you’ve got the combined loudness meter, you don’t need a VU meter. The loudness meter is super high tech, lots of graphs, numbers and lights. But let me give you an analogy: When mobile phones first came out, loads of Millennials, ditched their wrist watches and embraced the new tech; if they needed to know the time, they could just look at their phone. But as time passed, they started wearing their watches again. Why? Because they realized that they didn’t want to find and open their phone to find out its 19:48:32, they just wanted to quickly glance at their watch to see it’s about 10 to 8.
A proper analogue VU works the same way. When it’s properly setup, you can just glance at it to work out if you’re running too hot or not. You don’t need to stare or interpret numbers, a glance is sufficient. This keeps you focused on working with the music with your ears, not worrying about numbers with your eyes.