The only 24 hour endurance race I completed was with my B spec driver. 24 hours at Le Mans. Then the very next day my optical output quit working. Shortly after that disk read errors and wouldnt play some blu ray players. That event killed the PS3 after that event. So we purchased a new PS3 and this time with a 2 year warranty. So if it dies after the level 40 24 hour endurance race at Nurburgring, I get another PS3 for free. And that will be the last endurance race I ever complete. Well I cant say "I" its technically the B spec racer.
So if you attempt the 24 hour endurance races, dont be surprised if your PS3 starts having issues. Mine was out in the open and VERY well ventilated and still died. And was the slim which was only 2 years old.
I have to admit, having the "Mid Race Save during A spec" would be nice for sure. Too bad thats not available in B spec mode. Probably could have saved my ps3.