A helmet with an integrated rear light is a great choice if you commute regularly in urban or low-light conditions. The biggest advantage is convenience—you'll never forget your light at home or lose it between rides, since it's always right there on the back of your helmet.
That said, there are a few trade-offs to keep in mind. Integrated lights add a small amount of weight and require regular USB charging, so you'll need to build that into your routine. If the light stops working or the battery degrades over time, it can be difficult or impossible to replace, meaning you'd lose that feature entirely.
Also, built-in helmet lights are typically not as bright as dedicated standalone rear lights. For serious night riding on unlit roads, you'll still want a separate, high-output rear light. But for city commuting with streetlights and moderate traffic, an integrated light provides solid visibility and one less thing to think about when heading out the door.