I made a big mistake upgrading the AM GT3 using so much GC. It sure made it easy to complete "The 500" and made if more fun to drive but I found out rather quickly that it didn't matter how much I upgraded the PR on the AM since the you can't run the last three events of Masters of Speed without owning "all" the cars in the series. I got caught napping on that bit of detail since I don't think there's another series that requires all the cars to progress at least to 75%? I may have saved the GC and purchased the 2014 911 instead? (shrugs) Dang...can't even get to 75%.