I have used SMW for many years for routine maintenance on my a/c and heater.  I knew the unit was old, but for years they have been repairing it as needed, until finally they gave me the opinion that it needed to be replaced.  I had to wait a couple days for the scheduled replacement, and during that time the a/c died completely.  Scott came out to my house in the evening, just to see if there was anything he could do to get an extra day or two, but no luck.  They moved up my installation time, and there was no charge for the extra service visit.  I love my new unit and would never consider using any other company for my a/c needs.