If you only switch out 1, you are probably gonna feel a difference in certain moments as the tread differs between models. If you switch out both from the axel where you blew the 1, you probably wont feel a difference. I'm currently running P Zeros front & rear but their actually a different P zero model and haven't felt anything at 140mph+ too.
And just to clarify: 4s did not replace the 4. 4s replaced the pilot super sport as the main high performance tire (sport cup 2 being ultra high performance) and the 4 replaced the 3, which are still sporty but more orientated for longetivity rather than high speed performance, as in most cases when it comes to tires, it means higher performance=lower longetivity.