I think that, if their engineers are suitably qualified, then there is not an issue.
They are responsible for ensuring that the vehicle is safe and roadworthy and, if it is not, then they are liable for the error and any costs incurred in their failure.
I suppose my concern is that poor calibration could result in a system that works but is degraded in its performance whilst not be immediately obvious that that is the case. I’ve asked them to provide documented proof of the calibration but it seems all the bit of paper will say is that it’s calibrated. I was rather hoping to receive something that detailed calibration results versus specification requirements.
Had a chat with the windscreen guy at Autoglass when they replaced mine a couple of weeks ago. Apparently the iPace is really easy to replace the screens on - the camera isn't attached to the glass at all and remains in place. The windscreen is forced into the correct angle and position with square pegs so they can't mess up the angle at all. Re-calibrating apparently is automatic and they took the car for a short drive so it could calibrate itself (not sure if it needs setting into a specific mode or not).
My matrix LED lights still work fine, so the camera is calibrated well for those. I am not as sure on the traffic sign recognition - it's missed one or two signs but I'm not sure if it would have spotted them before replacement. Not been able to test lane keep assist either.
My only complaint is it took 9 weeks for them to source an official Jaguar replacement screen, but I guess since I'm MY21 my car is one of the few with one windscreen mounted camera as the pre MY21 and the MY23s all have 2 windscreen mounted cameras.
The other thing to keep in mind is that Jaguar themselves don't do windscreen replacements, so the windscreen specific ones are your only choice and the only ones trained.