What measures can I use to know whether my insurance company is good or bad?

The amount of Market shares and the number of claims settled.

I agree Mr. Abudrhman Zughaibi answer and add the undermentioned two points :-

1) Also the insurance company financial position and be market well recognition and known is important .

2) Also the arrangement of the reinsurance program with good international reinsurers to obtain good reinurance coverage and protection to enable the insurance company to pay any claim and fulfill its obligations promptly.

I think these two points will be in favor of the insurance company.

Thanking you..  

Well when it comes to service, you can judge. Service starts right after you sign the contract till you get the policy documents and when a claim arises.

Dear sir,

              You can judge the company by knowing its Solvency Ratio track record.

On a personal level, an insurance company should pay it's claims fast, be responsive, offer great services for its clients, provide extended coverage when requested