I mean no disrespect and certainly might offer some valid advice, but BEST is relative to a particular situation, when it happens.
Two Pit Bulls guarding your entries could be extremely effective and might cost as much or less than a company.
Broadview has lately taken over another company and in our economy that's common even with banks.
One of the most important features any "security company" can offer is an immediate response to a well functioning alarm system, which could mean NOT allowing access to intruders who might look for visible phone lines to cut, and certainly some will disregard signs no matter how many ADT things you post around.
The job of a valid security company is to monitor those under contract and their office might look like an Airport in the ATC section and be as busy and important. Their other position should be to call your given numbers rather than have you call them.
Certainly response times can vary with alarm companies and those relating that info to law enforcement agencies, but that should be your homework. "How soon can I expect a proper response to any incident" Given the fact that the alarm should be faster than even a 911 call made by you.
There is of course, issues you probably have to consider such as cost/versus value, which might mean someones life or property. Another issue you might inquire about is to the local government and that would include Police/Sheriff, etc. on stats, and various response times, and what is solved and what goes unsolved or even accepted in your area as "OH WELL?" I'm not at all trying to categorize by any area, and certainly not by any economy or ethnicity in that area, but I think you need to go beyond just a security company in your research. IE: I live in a large county, ill manned truly, in any sense of rapid response by law enforcement. That isn't to say that crime is more prevalent here, but it might be that a break in, and/or a slow response time is known by criminals, and taken advantage of.