We have experienced very weak, diffuse reactivity with Selectogen I, Lot VS981, exp: 01/03/2017. We just began them using last week, and right out of the box, we are having repeated problems with the first screening cell. We opened a new set, with the same results. I called Ortho on Friday, answered questions and followed up on suggestions. We have had problems in the past, but not with a brand new shipment.
We use only manual gel right now, but are hoping to get a Vision soon. This does not bode well for that encounter!