The drone business is going to grow much faster, IMHO. Especially if battery technology makes some significant milestones in the coming years. Electric quadcopter drones that can fly for 300 miles before needing fresh battery packs. You can bet police forces in every state in every nation is going to be buying these things. Meanwhile, gas powered drone use is ballooning even still (although you need a runway somewhere conveniently nearby to take off and land).