I have had absolutely no problems with the co op young driver policy. I took it out myself when I was 17 and the price was excellent compared to other insurers. I haven’t had a driving discount and my score is mid-low, but I do drive like a bit of a nutter, sometimes 20mph in excess of the speed limit (not in residentials, calm down mothers) and have had no issues with warnings or fines from them. Only issue with the driving score is that it penalizes you for driving past 11pm. I have had a fault accident on my policy, which I admitted to fault and they handled it very quickly and with absolutely minimum intervention from me - even though I have done almost double the mileage I quoted them (didn’t expect the mileage added by having a girlfriend). I chose not to renew as I want a non black box policy for peace of mind although their renewal quote offer was excellent. I can thoroughly recommend them if you are 17.