Brushless systems are usually more efficient and capable of higher performance, but brushed systems remain useful for cost control, smooth low-speed use and beginner products.
Brushed
Brushed motors use physical brushes and a commutator. They are simple and inexpensive, but brushes wear and high-performance efficiency is lower.
Brushless
Brushless motors electronically switch motor phases through an ESC. They generally offer greater efficiency, power potential and durability, but system cost and battery demands may be higher.
Do not judge by motor label alone
Vehicle gearing, battery voltage, ESC limits, weight, tires and drivetrain all influence actual performance. A brushless badge is not a substitute for evaluating the whole platform.