Cornish DIYer

Dear All, We are currently trying to choose the best type of standing seam metal roof. It's a veritable minefield!!! Initially we landed on the Prefa Prefalz Aluminium type, but then were told it now had a 16 week lead time. We also looked at GreenCoat PLX, but are unsure whether Steel is as good as Aluminium. Can anyone recommend any products that have a reasonable cost per metre squared and that don't have a very long lead time (we want to install around the end of January). Thank you so much in advance! Cornish DIY'er :-)