I used Shamrock to replace one of the units on my house, and to give the other unit a tune-up. They did a great job on both tasks, the process took less than half a day and the delivery of the new unit, the installation and the disposal of the old unit went very smoothly. They took the existing unit apart and gave it a very thorough cleaning and there's a noticeable difference in how cool the air is and the efficiency with which it works. Definitely would recommend!