WHICH ROOFING MATERIAL IS THE BEST?
The answer to this is simple: No roofing material is the 'best'!
They will all 'do the job' well!
Broadly all roofing materials - whether you are looking at concrete and clay roof tiles, or man made and natural slates for a pitched roof, or felt or GRP fibreglass products for a flat roof, have all been tested to a number of British, EU and often International standards and will have all met and exceeded them - otherwise the manufacturers would not market them, and specialist roofing materials suppliers such as About Roofing Supplies, would not risk our reputations by selling them.
Most products have lengthy warranties, with service lives that usually exceed the warrantied life.
So, if 'best' means 'which one is the most waterproof' or 'which one will last the longest?' the answer is broadly that they are all similar.
However if you are looking for 'which roofing material looks the best?' then only you can decide that as beauty is in the eye of the beholder!