If good quality stainless steel grommets is important to you, it may be worth you doing a simple 'magnet test' on your chosen product. If a magnet sticks they are likely to be only stainless coated which may result in an unsightly corrosion problem in the near future. Undoubtedly there are applications where stainless steel is a necessity but often a high quality solid brass grommet will be sufficient and more economical.