head gaskets

doing a mild perf. 318 build up, zero decked pistions, 302 casting heads. question is, what head gasket have anyone seen to hold up the best? i have a set of mopar paerformance steel core .40" compressed head gasket new in pacake, but have been told don't hold up to daily dringin and have trouble sealing for any length of time? true? or should ijust use a good compostion gasket perferably with a wire core around the cyinders. lie mp... p4120093? will have a small shot of 75-100 hp nitrious in future. any suggestions? reall concerned with the coolant sealing.... live in az gets hot here....