Well if quality is your priority then go for the brand Fujisash.
Solid construction with cleverly concealed hinges, exceptional
sound proofing, minimal air/odour transfer and water sealed.
Its Japanese technology with a factory in Butterworth and a sales/
marketing office in SS23 Tmn SEA PJ.

I nearly opted for Fascina which is Upvc construction but decided to
go for Fujisash due to the savings. Nearly 65k was spent on folding/
sliding doors & windows for my hse reno.....no regrets.