For air, water (+chiller) and mild phase a chip with average leak & VID seems to be best.
There are quite massive differences between the power consumption (= heat) between the keepers & leakers.
The least leaky chip (happens to have the highest VID too...) I got has over 10% lower power draw than the one which has the highest leakage (lowest VID...).

The chip with lower leakage does better on air with 4CU/8C configuration, while the high leaker beats it hands down with only one core enabled. The "keeper" also runs 6c cooler at the same clocks, even the VDD is 0.1V higher.