I see what you are saying here, but Maxsteam is absolutely right.

Excess insurance is only worthwhile if you claim on your car insurance. But...if you claim on your car insurance, your premiums go up the following year.

So....although you save £60 by insuring your excess, any claim will put up your premiums and negate the benefit from having it.

It has to come down to one question...

How likely are you to claim on your insurance next year? You obviously don't know this, but you do know that not taking out the xs ins will save you £95 which can go towards any potential claim.

Personally, I don't see the point...