Oil pressure gauge wiring

I borrowed this off the user 'Chudd' its a very handy picture! So is it always best to use the thread on the side of the cylinder head?

I'll explain a little and let you decide.

At the filter mount the passage where the switch is mounted (high pressure) reads pressure right after it leaves the oil pump. On the side of the cylinder head the low pressure switch is located at the end of the oiling system. If something were to happen, like you spin a bearing or spring a leak, the location at the cylinder head will indicate it as will the filter mount location. Difference is that the location at the cylinder head will begin showing a pressure change as soon as the problem starts and the filter mount location will tell you there is trouble when there is not enough oil on the pan for the pump to pump. Your call.