We have had many average speed cameras is Scotland, for a number of years. The Forth Road Bridge had them for the duration of the building of the Queensferry Crossing. The A9 has long sections of average speed cameras, linked by short lengths of dual carriageway to permit overtaking.
The average speed cameras in Edinburgh are unusual in that they are in an urban, built up area.
Personally, I don't have a problem with speed cameras, "Stealth" or otherwise. We have loads of Camera van sites round here and people regularly get "booked" by them.
If you don't speed you don't risk a speeding ticket.