Board Thread:Game Discussion/@comment-183.90.36.45-20180512060709/@comment-2405:204:B305:2C6D:401C:1632:8921:C135-20180512080333

There is no point buying the RSRs at showcase prices unless you have GCs to spare. The sales are rare but they do come up here & there. Have patience & pick them up then.

As for the rewards for McLaren Generations, they will be the same as now in 6.3 (a total of 80gc) so it doesn't matter whether you want to get it now or then in terms of payout except that you'll be earning a "fistful" of gold (extra 7gc) in the next update upon 100% completion.

The difference is more on the gameplay rather than the rewards. Currently, the P1 GTR is enough to get you to 91% with R$ and unlocking High Tech Legends, Hypercar Charge, GTE-Pro:Chevrolet and Porsche, GTE-Pro:Ford and Ferrari & Group C:Championship. Update 6.3 will additionally require McLAREN P1™ & the McLAREN 720S. Since you do not have the 720s & I am not sure whether you have the P1 or not, but only the P1 GTR will no longer get you to 91% from 6.3 hence IMHO getting to 91% with a single car is a bargain & you should get it done with.