Avoid at all costs, the work is not guaranteed and you will be told - no one else is complaining - if you raise any safety concerns
Parkers undertook an upgrade to my staircase balustrade. Two large glass panels were installed and initially looked great. Soon after installation the panels started to move and squeak when anyone used the stairs. Now two years later it is clear that the glass panels were not installed correctly, the panels are now moving because the two small wooden wedges used to secure the large glass panels are not secured in place with any fixings at all (not even one screw!). They are now lifting, with the glass movement becoming worse. No rubber gasket was used to take up any movement either. After approaching parkers I was told they are too busy, after waiting then chasing a response I was told "I've installed loads of these and no one else's complained". This companies arrogance is unbelievable, I am now having to take the same route as others and take this company to court to cover the cost of a competent tradesman to re-install the glass balustrade (only this time using actual fixings and not relying on gravity alone to hold large glass panels in place).