The db01 will have less corner speed than the 501x and the 501x has less corner speed than the 511 and that is the only big difference between all those, from a serious racing point of view the 511 is the one to have but they are all capable cars at any level, but you will need to spend a bit extra on better shocks etc..for the db01, so why not just buy a 511 and you won't have to buy anything extra, apart from a bodyshell
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