Outside lights just not fit for purpose

In 2013 I bought 20 Puzzle LED Exterior wall lights manufactured by Astro Lighting Ltd to be fitted to the outside of my new build home. These lights are billed as IP44 rated, and came with a 3 year warranty. They say they are suitable for environments over 5 miles from the coast, so as we're over 50 miles from any coast I felt confident that these lights would be just what we needed. They were not cheap, but strangely I was also reassured by that too.

How wrong I was! The light casing is made of steel, and has a mat black finish. This started to fade within 12 months, and has rusted since then. I painted a couple of the lights after 14 months, and whilst these have not rusted on the outside they too are rusting on the inside. the remainder are all now rusting. Two of the lamps have also failed altogether.

I should have reported my concerns within the three years to trigger the warranty, but I didn't and only reported my dissatisfaction recently. I provided photos to show the very poor condition of the lights, but Astro's only offer so far is to allow me to buy some more at a discount. Why would I want to buy more products which aren't fit for purpose? I want to warn any prospective customers to give this product a wide berth as it is patently not manufactured to a standard where it should be outside at all, however far from the coast you live. It's a shame they haven't paid more attention to the finish, as with a modest amount of attention to rust prevention I'm sure these lights would go the distance without issue.