Why? It sounds like the wastegates are adjusted correctly on your car now... why don't you see what it does? Are they just not producing the power (boost) you had hoped for?
It seems like a big step to switch to new turbos just because of a minor fixable problem like this. Perhaps you should give it some time until we work the bugs out and getting them operating like they should. I still think they are capable of 550+ whp with the right amount of boost, tuning and supporting mods.