In what situations would you want to use a brushless motor over a brushed motor?
If you have the money, wherever you can.
Brushless motors are lighter
More power efficient
More power for a given mass
Smaller and easier to package
The money difference isn’t even that cut and dry. A NEO and a Spark Max is $115 combined ($40 NEO, $75 Spark Max), and a CIM with a Talon SRX is $123 ($33 CIM, $90 SRX). The Falcon 500 is the most expensive option at $140, but that’s not much more than either of the other options.
Don’t forget the integrated encoder in your list of “pro’s” though. If you wanted to add an encoder onto your system, you’re looking at another $40 for an SRX mag encoder. Even with a CIM, a Victor SPX, and a mag encoder, you’re still looking at $123, which is more expensive than the NEO + SparkMax.
That said, we have a few brushed motors on the list this year. Namely 775’s on the shooter because of their high speed, relatively high efficiency and power, and their size. Running a brushless motor out to a shooter means running either CAN or the encoder wire a long ways, which we’re still reluctant to do.
in FRC use, brushless motors are generally smaller than brushed motors providing a tad bit more room in your robot, they are also lighter, and run just as well if not better than a brushed motor of the same style (for instance CIM vs. NEO) really your only con is you can’t plug it straight into a battery like a brushed motor due to how a brushed motor works (really shouldn’t plug any motor directly into a battery but you know if it’s an old brushed motor, braced and the wires are held properly you are about as safe as you can be for testing purposes)
Brushless has a higher power to weight and power to volume ratio. That being said, you aren’t going to lose a match because you’re using brushed motors.
You won’t lose a match because of a brushed motor per say but technically you could lose a match because of the weight savings.
The weight savings could potentially open up areas where you could add more things to improve your robot.
That being said, you really need to be pushing your design to the limit if the weight saved is gonna make a big difference. Driver practice along with consistency is more important and you can 100% get this with brushed motors. If you have the money though, by all means, I encourage you to go brushless.