Hi i'm about to fit my hard top and was thinking about using neoprene instead of genuine foam ones anybody know the sizes or any experience of different materials that have worked Cheers

Probably doesn't matter at all but I would put a bead of mastic on it anyway.

I used rolls of neoprene in varying sizes. I can’t remember exactly but got the sticky backed ones that made fitting a doddle.
I do remember the rear side panel to tub worked out at a fair old size. Somewhere around 25mm x 30 so it sat snug in the recess. Although the adhesive gives little protection to leaking it’s fantastic at keeping the seal in place while you manhandle the roof back on.