Let me give you the TL;DR right now. Worst game ever.
I played a single race (yes I made it that far, so I earned the right to judge the game). I immediately remembered a really funny parody of the FPS games of that era. Duty Calls. Now for those who aren't familiar with this name, let me describe it briefly. Duty Calls is a parody of many FPS games, based on Call of Duty franchise. It was made as an advertisement for Bulletstorm, whose trailer played at the end of this mocking game, with the message being "nowadays FPS are like the one you just played, here is what it is supposed to be like (Bulletstorm trailer begins)". Flatout 3 felt exactly like that. "Here is a crappy racing game to depict everything wrong with racing games today, and now, real Flatout 3 begins where you get to have super fun just like you had in the previous games, even ultimate carnage, which was basically flatout 2 re-sold to you suckers, but turned out to be pretty good anyway". Disappointment begins... It was no joke, no "real" Flatout 3 started. Flatout 3 really is the horrible.... ummm..... I can't really say that it's a game.... It's...... a software...... where you control...... no not control........ more like........ watch a car that was based on the drawings of a drunk newborn...... cruise in a city designed by a band of autistic apes...... and think that you contribute to its behaviour by pressing certain buttons on the controller.
Ok jokes aside. Graphics are extremely unfinished. Simple and undetailed, but not intentionally, just due to lack of skill and/or effort. Just look at the screenshots. At the first glance they look pretty decent. Now look closer. Inspect details. Don't tell me it's a 2011 game. Compare it to DiRT or just Flatout UC. You will see it has horrible graphics.
Controls just don't matter. You don't feel in control of the vehicle, not even a little bit. The car just goes vroom vroom. No realism, no control, no fun. For those who will bash me for looking for realism, just go play the previous games. You will see what I mean. Junker cars used to slide, drift, bump, etc. Now they just perfectly hover over the asphalt. When you try to turn, it either doesn't turn enough (if you're too fast), or turns successfully (if you're slow enough). It doesn't drift, slide unless you pull the handbrake. But if you use nitro when your car is aligned with the road, it just immediately and magically stops sliding and continues it's hovering over the road. Here is a short list of games that offer a better and more realistic driving experience: Asphalt 8 (iOS and Android), The Need for Speed (1994), FIFA '96. Also, I'm using a Logitech F710. When I set the controls to the gamepad, it stops working. If I set them to keyboard I can use my gamepad with xinput mode. ♥♥♥♥ logic!
Sounds. There are 4 sounds in total. One of them is the menu sound "click". Three in game sounds are "vroom", "bfffttt", and "dufff". Now "vroom" is the engine sound made by the cars engines. The sound was produced by a pair of bored game devs, that just made the sound with their mouth. I can almost hear one of them saying "screw the consumers, they will buy our games anyway", in the middle of the sound recording session, faintly hidden behind the sound of the engine. "bfffttt" is the sound nitrous makes, and the artistic creation of this amazing sound was most likely based on an air refresher spray. "dufff" is the collision sound used in every single collision to every single combination of objects. Again, it was probably made by devs dropping a heavy pillow from a distance.
Music. Literally non-existent.
Car tuning. Do you remember the simple, yet fun car modification system Flatout used to offer? It's gone. Here is the new system. "Would you like to tune the car?" [Yes/No]. If you choose yes, then the car is "tuned" by standards seen fit by the devs. I swear to god, I am laughing at the stupidity of this, as I'm writing, while crying on the inside because it isn't even slightly exaggerated. Ladies and gentlemen, a new era of modification begins where cars are either "tuned" or "aren't".
Please just watch a single gameplay footage from any source. Even the official game trailers give you an idea of how ridiculous this game is. Don't take any of my word for it. Just look it up on youtube yourself. Watch some videos and see for yourself that every single sentence you read here, is describing that video.
I bought the Complete pack for 10$. I am not sorry because I love Flatout games. I played them on PS2 for long hours. I am glad to have 1, 2 and UC in my steam library for just 10$. But if you want a Flatout game, just buy UC. 2 was better than 1, even though 1 was a pretty solid game itself. And UC is just a graphically and realistically superior game, that is essentially Flatout 2 with additional content.