Despite my expectations, I got sucked in. I've been playing for a few weeks. The best part: I haven't paid a cent! Here's why I like it.
How the model works
RR3 follows the usual, FarmVille style currency model. There's a 'cash'-type currency that is relatively easy to earn and there's the more expensive currency. You have the option to pay real money to top up both these currencies. In this game, you can purchase almost anything with the cash - buy cars, upgrade them, service them and repair them. I have noticed nothing (except for car resprays) that can only be purchased with coins.
When you service your car (every few races, depending on how you handle it), you have to wait for a few minutes in real time before it is available for use again. Meanwhile, you can use another car to race in its eligible events. When you buy a new car, you have to wait for the delivery (sometimes up to an hour).
You can skip these real-time delays with the expensive coins. This is usually a bad model in my books. But I still enjoy the game without paying anything at all.
Why I like it
There is almost no grinding
Earning cash is pretty easy. After the first few events, every single race will give you a respectable sum of cash. You can earn a lot of cash without having to do races over and over. They unlock very easily. Of course you have the option of leaping forward to purchase expensive cars by grinding on older events. The racing experience is very fun.
It's a perfect simulation
I think that paying in this game is like cheating. The game is a very realistic simulation of a real racer. Of course the car delivery or service times are not very realistic, but they are still good for a video game. In real life, you can't pay money to get things done instantly. You have to wait for an oil or tire change. You have to wait for a new car to be delivered to you.
Of course there are people who would like to continue playing without the wait, but I really don't mind it. Besides, after the first few events, you will move on to purchase more cars. As others are being serviced, you can always play with your other cars.
The game does not consume you
This realistic simulation and free-to-play model ensure that you do not get completely addicted to the game. I prefer good pick-up-and-play games on mobile platforms rather than ones that require you to sit through long sessions.
I can play RR3 while waiting in a queue, taking a study break etc. When a wait comes up, I can put my phone away and play later. I do not feel constrained at all.
Again, others may have other opinions about this, but this is what I like.
Coins are not hard to earn
This game follows the Dead Trigger model. Dead Trigger is another iOS and Android game that does the free-to-play model very well in my opinion. Apart from getting a bunch of coins after every driver level, you can also watch 30-second advertisements now and then to earn anywhere from 1 to 3 coins.
I have still not used a single coin after a couple of weeks of playing (I treat it as a pick-up-and-play game), but even if I wanted to, it's easy to earn the coins for free.
If you haven't tried out the game yet, I highly encourage you that you give it a whirl. It indeed does the free-to-play model right while being a great racing simulator.