All the time,firm believer that motorists(car/bike/lorry) have more rights than cyclists - hands down. Word of caution/mind - stay on the standard line BEFORE the box starts .if there are whites lines & a camera (sling a look over your shoulder an up)...
If you're doing the same route every day, you'll get to know where the cams are along the way And besides that, a scooter can, mostly, accelerate quicker than a car from a standing start, mostly. But you will get the obvious beligerant drivers; just let them go. You'll still be ahead of the rest.
to be honest i couldnt say, i never pull into those boxes upfront for cycles. all i know is that all motorists inc motorcycles should stop at the first line, UNLESS the light changes to red and you already passed the first defined thick white line. myself i just dont go into them . looked up and police can air caution but usually its an offer of fine and 3 points on licence
No I do not use them, only be in there if it's an emergency as was the case today with a fire engine heading up the main road I wanted to turn on To be honest these boxes are a nuisance