Is there any way to confirm proper assembly?

I built a T15, an A12 and an N72.
All of them pass signal well enough, but because these were my first PCB board projects, I am stressing out over whether I put them together right and whether I am getting the full potential out of these preamps.
Is there any way that I can know once-and-for-all that these preamps were properly constructed and are functioning at 100%?
Tim, how much would it cost to send you all of them for a check-up?
All of them pass signal well enough, but because these were my first PCB board projects, I am stressing out over whether I put them together right and whether I am getting the full potential out of these preamps.
Is there any way that I can know once-and-for-all that these preamps were properly constructed and are functioning at 100%?
Tim, how much would it cost to send you all of them for a check-up?
