Speaking of iRacing.
http://jalopnik.com/5926673/how-the-right-video-game-makes-you-a-faster-driver
There is some truth to what he says but it is also pretty elitist. He probably tried Forza 2 on the Nurburgring and dismissed all console games because of it. he basically dismissed RFactor because some of the tracks were inaccurate. He never really gave it a chance. If iRacing really was that close to real life and GT5 was that bad then people like Forgetful and myself would be just as bad as all the other rookies. I'm running almost incident free races and Forgetful is challenging for wins. Compared to the leaders, my iRacing and GT5 times are similar. The writer of the article also recognizes but dismisses iRacings issues. No sim is perfect.
That being said there are definitely things that iRacing does better than GT5. GT5 doesn't really simulate proper engine braking. There is no need for heel toe downshifting. In GT5 you can downshift all the way to first and the magic ABS will prevent wheel skidding. Although in iRacing, I'm using the autoblip aid until I get better pedals. in GT5, curbs don't unsettle the car properly. You can hit curbs at speed that in real life would probably destroy the suspension. iRacing appears to be much more accurate. LFS was sometimes over reactive to curbs; hit a curb slightly wrong and the car tips onto it's side. A related issue is that the tracks in GT5 are comparatively flat and smooth. Driving in iRacing is much more alive as your car reacts to slight changes in the road surface as you would expect in real life.
I'm currently playing iRacing using my laptop. So far it works pretty good. Nvidia and iRacing have a contest right now where you can win a video card. I'm
counting hoping on winning that so I have an excuse to build a new system.