Any company that provides homeowners insurance must file an annual statement with the Department of Insurance in every state in which they are licensed. This statement is a summary of the company's financial operations for the most recent year. It should also include a balance sheet.
Checking your state's Department of Insurance Web site for this information is always a good practice. You can then have this statement open side-by-side with online home insurance quotes. You can see how the company is doing financially and what they are willing to offer you at the same time, and then make your decision.
Do this for each company you are considering and you can not only compare their rates, but also their stability. Then you'll be more comfortable to buy home insurance online. If either piece of information raises questions or concerns, contact the insurer and get the clarification you need in order to be comfortable making your choice.