Mix & match speed ratings, on the same axle?

[EllD90]

Right, so I've got Michelin Pilot Primacy's on my car. One of them ideally needs replacing. My tyres are 88V Extra Load. Would I be stupid to put on a 84V Michelin Pilot Primacy? (not Extra Load) It's a part worn tyre, hence the question. Would the grip/feedback be affected?

Thanks in advance!