The search for a ends with a simple choice: convenience (Steam) or DRM-free (TML Store). Whichever path you choose, you are buying into the most detailed bus economics simulator on the market.

"Low FPS despite having a good GPU."

To enjoy the game fully, you need a PC steering wheel (Logitech G29 or Thrustmaster T150). While you can download Tourist Bus Simulator and play with a mouse/keyboard, the steering sensitivity is difficult for precision parking.