Advice on BluRay burners and media

Hi everyone, so i have been backing up data/movies to DVD for years and
it's served me well, i know many will say optical drives and media are
dead but i'm in the camp that does not agree. I still back up to HDD
(both internal & external) and vital images and docs get uploaded every
24 hours (about 1GB) but i know full well one day a HDD will work fine
and plug it back in a week later and clcik of death so backing up to
optical media and just another safety net, so now i have that lot off my
chest on to the reason for the post.

What kind of burner to go for, but please bear in mind that reliablity
of the media is high up on my list, i think i have heard of something
called "M" but hear the media is rare as rocking horse sh1t and it ain't
cheap but i'm confused by drive type and media types, for example i see
some media goes from 25GB to 200GB, the drives themselves Blu-ray BD-RE,
Blu-ray BD-RE Dual Layer, Blu-ray BD-R Dual Layer, Blu-ray BD-R and the
usual RW formats which i doubt i would use much but i guess could come
in handy sometimes, i also see 4k versions coming online now.

I have done some googleing and found a few articles but none mention the
media side of things and was hoping some of you folks could help me out
a bit.

TIA

Jim