Jonas,

on a stock T25 there is no boost controller OR WG actuator that is going to make it hold 14 psi all the way out to redline. it's not possible. the compressor is only 24 lb/min it cant flow much more than that.

as for boost creep.

it any boost controller will have a littel bit of boost creep in different conditions. the key is to not have your car tuned so close to the edge that if you have a bit of creep it is going to grenade your motor.

I have little to no boost control issues with my AVC-R.