I bought a turbo from them almost two years ago, when I first installed it I couldn't build boost either, I figured out that the actuator arm needed to be adjusted tighter. A turbo with no seals and a leak would still build boost just later in the rpm band as long as the compressor wheel spins freely. I don't think the "leak" in your turbo bearing is even relivent to your boost problem, A leak that kills your boost that much has to be after the turbo outlet. I bet that if you put at least 2 turns on your actuator arm you will build boost just fine. Have you started the car with it installed and tried to build boost at idle?