If you are a big fan of driving games like Gran Turismo, Dirt 2, Need for Speed Shift and some of the PC's more hardcore sims such as Live for Speed then do yourself a favour and save up for this wheel. I've been using this wheel for about a week now with Need for Speed Shift (which is surprisingly an excellent game) and Gran Turismo 5 Prologue.
Initially I found it more difficult to contol the cars using the wheel, but once you get over the alienation of not using a control pad it's actually much more fun and intuitive (especially if you already drive). Driving the cars has become much more involved, and once you start getting the hang of things like feathering the throttle when the back end starts to step out round corners and quickly applying opposite lock to correct the slide then you really almost feel as though you are driving these high performance cars. Switch to the in cockpit view on either of these games (which is excellent on both), and it really helps with the illusion and game immersion.
Its really strange, but after a decent session using the wheel (and pedals/gearshifter of course) and then driving your real car, everything feels very strange - being able to feel the inertia and road surface through the tyres/steering wheel seems much more pronounced, almost alien, because you can't really feel these things realistically when using the G27. It's almost as if using the G27 is real driving, and driving your car is becoming this weird new experience! It's a very odd sensation, but one that is testament to the G27's usability and pseudo-realism.
I really think, that to an extent, using the G27 could go some way to improving an amateur drivers ability to drive a performance car around a track. Obviously you don't get a realistic sense of the forces involved as you go around a corner, or the feeling of the loss of grip through the tyres but apart from that I really think that certain aspects would translate. Maybe I'm being naive, I've not raced on a track myself, but I've owned a few different high performance rear wheel and front wheel drive cars (between 200 and 300bhp) and explored the limits of their grip (on private roads of course) and in my opinion using the G27 isn't a million miles away from driving enthusiastically in real life.
The long and short of it is that I am delighted with the G27 wheel set. Yes it's expensive, yes they have ommited a few features that were on the G25 - notably the ability to change the H-shifter gearbox to sequential shift like you have on touring and rally cars, but honestly, it's still a fantastic product. The movement of the wheel is very smooth and quiet (an improvement over the G25 apparently) and the gearshift isn't that noisey either. I would have liked a bit more weight and feel to the gearchange like in a real (decent) car, and possibly made the throw a touch shorter - but really that is nitpicking. All in all it feels like a great quality product to use, the best peripheral I have ever had the privelege of owning.
One thing to note though, it is only compatible with PC and PS3, no Xbox-360 unfortunately.
If you are thinking of taking the plunge, I say bite the bullet and go for it! Get yourself a few quality racing titles like the ones I have mentioned and you will have a great time learning how to really drive! One small tip, when starting out I'd say put the force feedback levels down to near the bottom of the scales within the games that you are playing. When starting out sometimes it seems that high force feedback levels really works against the learning curve - I found that I was having real trouble just driving in a straight line, yet alone tackling corners. I was just endlessly fish-tailing down the road due to over correction of oversteer! As soon as I put the feedback levels down I found it much more manageable and learning to control the car became so much quicker! Some people will pick it up quicker than others, I've always loved racing games so found the transition pretty quick. Don't get frustrated if this isn't the case with you - just make sure those feedback levels are nice and low and keep racing, keeping your arms and feet moving fast. Don't be afraid to be a little rough with the wheel and pedals - they are built like german tanks. I'd say try be a little sympathetic to the gearbox, although it is quality, I reckon it could potentially be the weak point with lots of misuse.
Above all, if you do get one.... have fun! I'm sure you will. Also, I know most of the racing games say this as they start up, but don't be tempted to try and drive your real car like you drive with the G27. I used to drive like a complete idiot when I was younger, and I've been in some pretty nasty car crashes - very lucky to have come out with minor cuts and bruises. I've seen plenty of cases of people who have not been so fortunate, it shatters peoples lives. In my opinion everyone breaks the speed limit now and again, but there is breaking the speed limit and driving like an idiot. Always have in the back of your mind the questions, if someone steps out in front of me, or if someone in front of me slams on the brakes will I be able to stop in time? There are so many absent minded drivers on the road, often it's people who have been driving for years and just don't care any more. Take pride in your driving, it's a continual learning experience. Learning to ride a motorbike makes you think about these things so much more (if you have a brain, and don't have a death wish).
Well, enough from the voice of experience.... go get this wheel and have fun!