xperia sp rom [need help] topic

HI,
i have an xperia sp i have updated to 4.3 (12.0.A.1.266).Lags,Slow,Restart daily...
i will waiting for a correctif update (12.1.A.1.192) .. If no I will Downgrade to 4.1.2 but which one ?
which is the best Rom for Xperia Sp PLease i need help !!