Screws also have several grades of quality. Cheaper ones are often made of softer metals like aluminum or lower grade steel that are prone to corrosion and rusting. For higher quality screw look for Hardened Steel, Stainless Steel or Titanium screws in ascending order of quality and price.
As for impact drivers, I would recommend Bosch Professional (Blue), since its a reliable product and easily available in India. Avoid Bosch consumer brand (Green), it is not the same as Bosch Professional and held to a weaker standard: [
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For a detailed shootout, I would suggest watching youtuber Project Farm's video about impact drivers. He always has elaborate test methods and tests almost every possible use case.: