Four basic problems with this roofing system:- 1. FortunatelyTruely PVC were very helpful and understanding when I had to ask for replacement panel as they had not obeyed the basic cutting position restrictions stated clearly on each panel. Result was panel was unusable as edges colapsed under pressure of fixing bars. Cuts were also very crudely made. 2. Panels were warped so I had to fit loads of screw down fixings to pull them flat. 3. Snap Down bars would jump out of channel every time the sun came out. I am hoping the addition of many fixing screws will resolve this.. 4. Panels would creep down slope of roof as they warmed/cooled each day. Result was end caps breaking off and gap opening up in roof. Screwing down has resolved this. 5. Aluminium edging tape was very badly applied. Not folded over sides in many places. Stuck onto protective film in many places as this had not been cut back properly. Damage in several places. I could go on to list more less serious issues, but will stop here. Finished joj seems OK now, but would not choose this product again. Nothing like the quality of my old panels, 25 years trouble free. On a psitive note, the thermal properties of the new panels if very good. Dave