Oil Pressure or Oil Temperature Gauge? What's more useful and Important?

[sierragrande71]

Hey everybody, I have slight dilemma I'm unsure what gauge to use on my aftermarket gauge cluster. I have 3 3/8 Autometer Phantom Oil pressure gauge#5829 and also a 3 3/4 Autometer Pro-Comp Oil Temperature gauge#5510 and I'm not sure which would be more useful,vital, and most important. I like both of them but not sure which way to go. Any help is always greatly appreciated. Thanks. Sorry I'm unable to upload the pics of the gauges.