Thicker is always easier, but makes moving slabs difficult. Too thin and they may warp and spit. A balance is best, remembering to always think about the final product.
I usually cut at 3” as that gives plenty of spare in case of movement.
However the wider a slab is, the thicker it needs to be cut, due to the structure being glued together by it’s own lignin.
at 120cm/4’ wide 3”-4” is recommended, at 5’-6’+ wide, I would suggest 6”/15cm thick.
What are your experiences?