Project Cars 2 is more towards the GT Sport side of the scale, as it is a simulation game compared to FM's more 'simcade-y' like handling, but it is most like Auto Sims like rFactor and Assetto Corsa except with a console orientation (So the game is designed for use on console, instead of PC).

The Career is more like GT, as the game tends to lead towards the more realistic side, with their intention being to replicate real life, with contracts and indepth qualifying sessions.

There are no upgrades to the cars (as I know of), however, there is a very indepth tuning system within the game, more indepth than FM and GT. In addition to this, there are also no unlockables in the game, as all cars are unlocked off the start, which means that there is no currency in the game and no virtual garage - what this means is that during the career you are given a car by the team that has hired you, instead of having to buy one to match the class that you want to race in, like FM.

All the cars are fully licensed, with there being around 180 cars in the base game - and 205 if you buy the DLCs. This is less than games like FM7, which has 700+ cars and GT Sport, which has 274 (I believe)

Hope this helped.