I am another happy AT customer. But you need to define your requirements a little better.
So far, you are saying you want a lightweight plate that will stop .30 AP and is light weight.
do you mean .30-06 AP? If so that pushes you toward something in an NIJ level IV which tend to be heavy. Or do you mean .308 AP or 7.62X39 AP or 7.62X54 AP that opens up a number of other options. Are you actually seeing .30 CAL AP rounds?
Do you require DOJ certification?
What are you going do be doing while wearing the plate? Contracting in Iraq, CONUS LE, classes and SHTF?
What size and cut do you need? SAPI, Shooter, Swimmer? That's driven by intended use and body size and type.
Given what you've said so far and what your budget is I'd look at HESCO and Velocity Systems.