5 psi wastegate spring so I can tune at as many pressure levels as possible. I have a dual port wastegate now and a solenoid, so I can run whatever boost I want, except lower than 5 psi. So boost by gear and all that can run as low as 5 psi.
(In theory. In actuality the damn wastegate flow isn't enough and naturally the engine creeps to 10.6 psi it seems.)