Awhile back before the 2.4ghz days when AM was still in effect big time around 2006, I used to work in a Hobby store and sold Hard Bodyz roll cages. Just some points...

Could be used without body, or even zip tie body panels on. If landing paint side down, the body would get damage from being pinched in between cage and ground, prone to grind holes.

AM radios sometimes glitched bad with cages. Check antenna contact.

It did add some weight, and was helpful on my Revo to keep front wheels on ground.

If the cage front was in a wedge, and not just a square shape, it would push the vehicle lower to help protect parts when it jams under a parked car, THAT IS if the front bumper was low enough before entering under parked car.

Get a roll cage that is higher than the top of the chassis and parts. Some guys had cages that the motor would stick out.

Roll cage on XTM Mammoth.