The nostalgia of playing Gran Turismo, including some of the greatest fun in gaming and also most frustrating moments. If you expect to unlock everything within the first few weeks, you will be disappointed. The 4* review shows how good the game is and could be, given the extent of some issues.
The driving is awesome and the physics are a big improvement. NSX Type-R '02 with no tuning is a highlight so far. However, sometimes the physics don't always feel perfectly implemented. This is understandable with the huge variety of different conditions and equipment.
The AI is defintely improved from GT6 and older titles. However, most races are still rolling start with you starting at the back. The car in 1st place starts way out in front and opponents tend to be much slower than you, if you use a car as quick as they suggest. Whether the race is easy depends on the number of laps and if you can avoid crashing into a slower car parked on the apex. Then suddenly you get a race where a fully tuned car with wings starts in first and you need to drive qualifying laps for 5 laps only to finish 3rd! Sometimes in wet corners the AI is like Senna and in some they are like an old granny.
Getting all the Gold licences is a nice challenge, one S test in particular! I've only done a few missions and enough Cafe events to unlock a good number of circuits but there is a lot to keep you busy after a few weeks personally. I haven't even touched online apart from a few private lobbies.
Some of the main issues are being addressed according to PD, but the recent update was disappointing when also released with the poorly balanced microstransactions. However, I'm willing to give them the benefit of the doubt given their track record. The grind hasn't even been a problem for me as I get most fun from driving JDM cars and tuning them lightly rather than buying all the fastest and rarest cars. The lack of fresh cars in Used Cars and always winning 5,000 credits for Roulette wheels is very annoying.
The main issue not yet addressed is online only single player, which is a big problem and should be fixed. I live in a city with fiber optic broadband and I still get disconnected during single player races.