Hi,
I'm not writing this review because my family use this.
I do manufacturing of cooker whistle and vent tubes. For marketing it's tendency to go around all cooker manufacturers. All together I have visited most reputated companies including ttk so call prestige, butterfly and many more. Most of then uses their own way of manufacturing and quality control.
Ttk being one among controlling quality at fullest. If anyone not aware, prestige comes at highest share of market in cooker industry and home appliances.
Manufacturing has faults and defects. It's uncontrollable to stop manufacturing errors, but can avoided by filtering out at dispatch section. Many company has tolerance criteria to push for market. Many reputated company have strict rule to 100 percent and some with 90 odd percent. There are chances we pick that 5 to 10 percent of piece which being pushed in market considering small defect and within tolerance.
Complaints might found in some at many reasons., one with less complaints better is the rejection tolerance level and better the product. And prestige is one among them.
It's taught form the person who personally visited the manufacturing industry.