This game strikes a great balance between arcade and simulation racing and just has a solid feel to it.
After playing through the game, not having opponents to race against makes sense and doesn't hinder this type of racing game. What really makes this game is how it isn't a hardcore realistic simulation game and is fairly easy to get into if you've played other racing games. However, it isn't entirely arcadey either and has a good amount of depth.
The entire idea of the game is to race through a course on your own on roads that are just wide enough for your car. Before the race you can repair your car as long as you have enough time (repairing each part deducts the amount of time you have left before the race) and adjust your cars settings such as tires, springs, gearbox and steering. The game also gives you the info of the track, telling you how much of each surface will be on the track (smooth asphalt, gravel etc). The adjustments and track info may seem a bit basic to some simulation racing fans but I think it's great for this type of game. You don't need to know a lot about cars and tuning your car after a few hours of playing the game becomes very easy.
There different types of car classes (2 wheel front drive, 4 wheel drive, rear wheel drive etc) and the cars feel quite different between the classes and they all have a good feel to them. The surface that you're driving on also changes how your car reacts drastically as well. The different between wet gravel and smooth asphalt is noticeable and rear wheel transmission cars have trouble driving on off road surfaces. This is probably the best thing about Colin McRae 2005, is simply how the cars feel; the game strikes a very good balance between arcade and simulation and the physics for the most part are well done. The graphics look good and you don't need a good computer to play this game.
There are a few downfalls to this game. In the beginning of the game you will have a problem turning the wrong way on some split roads even when the one road is blocked off by tape. After being a few hours into the game, this problem disappears for the most part (but never entirely) but something should have done in the few tracks that have this confusion. The indicator that pops up, telling you how hard the next turn is going to be is also a bit off at times. For the most part its very valuable and well done but at times it pops up either too early or too late and at other times it will tell you it's an easy turn when in reality it's a lot harder to take on.
Colin McRae Rally 2005 is probably the driving game that I've put the most hours into than any other game. Whether it is or not, it's still kept me busy and I've had a blast with it. It's the best racing game ever and it can be a bit short on content compared to other racers but it's still a fun game with a great toned down simulation feel to it.