@Joe I had to make a claim 4 years ago (the first in 30 years) and when we decided to leave Motability I was concerned about the impact that this would have on insurance. I needn’t have worried.
Even though we cannot claim any ‘No Claims’ discount having been Motability customers, you can still input driving experience and claims history and it seems to give you the same sort of discount as No Claims Bonus would. As long as you have at least a full year claim free that gives you the initial big discount, with each year beyond that adding smaller amounts of discount. If you end up going down that route I hope that you will be as pleasantly surprised as I was.