If you knew how insurance underwriting works you would understand why not making a claim will only preserve your no claims bonus. One more or less claim unless for an exceptionally large amount will have little overall effect on how the scheme is burning in terms of claims against premium income. If you are lucky and the scheme is burning well then there will be little or no increases and maybe even slight decreases. If it is burning badly and this is common, then premiums will rise with the biggest increases in the areas of biggest losses.
I hope this helps people understand popular misconceptions where they think the renewal premium is only about them, it isn't, it is about the complete scheme, which is the premium to claims ratio of all people insured under the scheme and the claims rate for your particular insurance criterion.
It does pay to shop around as the claims ratios and claims areas do change per scheme every year and if you find one that is doing well then you can get cheaper insurance.