After receiving a few estimates this company was the lowest. Not by much, but by a little. The thing that put it over the top was the service. They explained exactly what would happen, arranged a plumber to come and do the work needed (other companies did not even tell me I needed one, let alone arrange for it) and co ordinated with the plumber to cause me the least inconvienience.
I gave it a 4/5 for satisfaction as there is a join where noticable and I don't know if that would have been with all companies or not. there is a small chip that they would come out to fix but I was waiting for a follow up 'satisfaction' call that did not come. It isn't major so I will not worry.