New flat roof. Mineral, chippings or solar paint?

My builder is about to finish a new warm roof single story extension next to an existing extension. The old extension roof is being stripped and upgraded to a warm roof too.
Both will have firings, osb, 90mm celotex, ply then 3 layers of felt laid as one complete roof.
I have been asked which of the 3 finishes I want, the builder suggests solar paint, the BCO suggests chippings may be a better long term bet with not having to repaint every 3-5yrs and nobody seemed to have an opinion on mineral finish.

The roof is North facing.

I could really do with some advice on which to go for please.

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The reason that b.c. insist upon chippings over solar paint is fire spread risk. If the flat roof building is close to the boundary then expect to have to lay chippings.
bonkers i know.

I'm well away from the boundry, the bco suggested chippings on a recuring cost basis re the repainting being often and expensive.

My present 3 layer felt roof with chippings has lasted over 30yrs without leaks but I would have thought that one of the 3 finish methods has most benefits?
Or should I just flip a coin?

best is mineral finish other 2 are out dated and dearer mineral does the reflective part

a neat mineral finish