Is 6WD actually better than 4WD?

On loose dirt, gravel and grass, yes: the extra driven axle puts more power down and helps it climb. On hard flat ground the advantage is small, and a good 4WD truck will be faster.

It is built for torque and off-road grip rather than top speed. Expect it to trail fast 4WD monster trucks on pavement but to keep moving where they get stuck.

What battery does it use?

It runs on a rechargeable hobby battery pack, and run time depends on the pack and terrain. Buy a second pack if you plan long sessions, since charging takes a while.

Are spare parts easy to find?

Parts support is thinner than for Traxxas or Arrma models. Check that tires, gears and battery packs are available before you buy, since six wheels wear faster.

Is it good for a child?

It suits older kids and teens who can handle a larger, heavier truck. Younger children may find it bulky, and adult supervision is sensible around moving wheels.