Decent car hire excess cover?

Hiring a car in Greece later in the summer and want to get excess cover insurance.

Comparison sites throw up plenty of offerings at vastly different costs.

Any recommendations??

Thanks.

Went with Swinton for car hire xs in Sicily..£31...a month ago.
Was not accepted by the hire company at Catania airport

Eventually paid £198 to include another driver and to cover all costs above £600 in the event of an accident
The hire company took the £600 from our account on Day 1 of 8.
The car was returned undamaged and the £600 refunded

The pick-up took 2 hours while all this was sorted as they would not accept a John Lewis credit card
Luckily we had a Monzo card with us.

We went for the cheapest car hire company ( 50% less than Hertz) and got a 2023 Peugeot 2004
It was a hassle but as I always tell moaners..'we could live in Gaza'