I could do with some advice from those with experience and knowledge in glass roofs! We have two quotes for the construction of a 6mx3m south facing conservatory.

Quote 1 involves an ultraframe roof with 'Thermaglass' manufactured by Custom Glass of Liverpool. The units apparently have inner pane is made by St Gobain of France and the outer pane is a bronze tint anti sun by Pilkington. Cavity is argon filled and has a U value quoted as 1.1

Quote 2 involves a K2 roof system but we are provided with 2 glazing options, either Celcius or K Seal both with a U value of 1.4 and I dont think either involve argon. Sales lady says argon filling is a problem as it can leak out and require refilling (how would you know?)

Can anyone let me know the pros and cons of these options and whther one is recommended above the other