Mechanical Warranty for Used cars worth it?

Been quoted 3k for mechanical warranty for 3 years for Lexus and 2k for Euro cars in Wellington. For other Japanese cars like Honda Mazda its 1k.

Why the prices so high for Lexus? It was specifically for a hybrid but the guy said it's for all Lexus.

Know someone that picked up a Mitsubishi from Christchurch and paid just 500 for mechanical warranty. Does the cost vary by city?

And is it worth getting a mechanical warranty in the first place especially for a Japanese car including Lexus?