I used to race on an online Forza group which I thought would be good but was too serious. You end up in a race with people all over the place (US,EUR,AUS) so the lag isnt the best, you can race for 25-30 laps and make a small mistake and two of you end up in the wall and get accused of deliberately taking them out. Yet a long term member can take a few cars out on the first bend and its an accident! Can't say I done much after a few races....wasn't the fact the top guys were ridiculously good as well so had no chance!!
I can only imagine Sim Racing is a step above this too!