The short answer is Yes!
For novice players or players coming from console to PC Aim trainers are indispensable tool to improve your aim faster. Experienced players regularly use Aim trainers to warm up their aim before matches or to keep polishing their aim and maintaining their progress.
Some players experience improvement that feels to happen almost overnight, while other players feel the improvement in their aiming comes gradually over a long period of time. There's only one way to find out what would be your case - start practicing your aim on 3D Aim Trainer right now! It's free!