Concrete worktop questions

Hi Screwfix,

I’m fitting my own kitchen and for the worktop am considering a DIY cast-in-place concrete slab using products from these guys (edge forms, suspended mesh, concrete additive, sealers):
https://www.concretecountertopsolutions.com/

Two questions:
1. Does anyone here have experience of doing this?
2. Anyone used these products specifically
3. Concrete to use? They’re an American firm and recommend…

“Sand Mix which does not have pea gravel in it but if you cannot get something similar, a regular mix is fine”

Anyone suggest some brand names / products of concrete here in UK which best fits that description?

Cheers