After the boiler in my rental property failed its annual gas safety inspection, I sought a number of quotations before settling with Gas Monster's. I contacted Gas Monster because I particularly wanted a Worcestershire-Bosch combi boiler from a local accredited installer with a ten year warranty. It is difficult to say what it was that led me to choose Gas Monster, as I neither met them beforehand nor felt the need to inspect the work once it was completed. However, I suppose it was a combination of the way in which they communicated with me, answered all my questions and the assurances provided by my letting agent that they were well thought of. My tenants have not made any unsatisfactory remarks about the installation despite having to wait for several weeks without heating before Gas Monster could offer an appointment to install the new boiler, which I take to be a positive sign. I expect to have an on-going annual boiler servicing and maintenance relationship with Gas Monster and would certainly use them again as well as recommend them to anyone else.