It's garbage. Because of the focus on microtransactions and "live service" online play, almost every aspect of the game suffers. Cars cost too much still, with payouts being weak. There's VERY little content. Like 1/3rd of what I expect out of a Gran Turismo title. You can complete almost all single player races in about 30 hours. Worst of all (other than constant reminders to pay real money for everything) is the online nature of the whole thing. If either the servers or your connection go down, the game is almost completely bricked, even while in single player content. Mid race and something goes wrong, BOOT to menu. Mid license exam, boot to menu. It's ridiculous.
And OMG, the layout and UI. Be ready for easily 6 button clicks to back out of a race to change a car or something. At some point it feels like they were trying to make the most aggravating and worthless Gran Turismo ever, and congrats Polyphony, you did it.