Lately, I've been using them on everyone, and using movement speed masteries.
i only use movespeed quints if i have to. for example, if i'm playing an ad carry that doesn't have an escape vs a team of highly mobile champs. they are useful for any situation though.
The way I see it. You get 4.5 from Quints and 2% from Utility, if you set it up like that.
Most players normally have 2% only, that's 4.5 higher than them.
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