Is this kit worth it over a cheaper brushed combo?

Yes, if you use the tools regularly. Brushless motors run cooler, last longer and get more work from each charge than brushed motors, which offsets the higher outlay over time.

Do the batteries fit other Makita tools?

Yes. The 18V LXT batteries fit the whole LXT line, including saws, grinders, sanders and outdoor tools, so the kit is a starting point for one battery system.

What is included in the box?

The kit includes the brushless drill driver, the impact driver, two 5.0Ah 18V LXT batteries, a charger and a carrying case. Bits and blades are not included.

How does it compare with Makita's sub-compact kits?

This kit is full-size and more powerful, but heavier. Sub-compact tools are lighter and easier overhead but deliver less torque for heavy drilling and driving.

Can the drill handle masonry or concrete?

No. It is a drill driver for wood, metal and plastic. For concrete you need a hammer drill or rotary hammer, which Makita sells separately on the same LXT batteries.

How long does a 5.0Ah battery last per charge?

Runtime depends on the task. Expect several hundred screw drives or a long session of drilling in wood per charge; heavy continuous use drains it faster.