I can only tell you from experience. Ive poured quite a few house slabs with it. My perimeter blockwork is always level at dpc with insulation and the dpm wrapped up over top. Lorry/lorries turn up, 2 or 3 of us with rakes spread it about in less than an hour, much easier than standard concrete. You fill it up till its to top of blocks all around. Someone goes over it with a dapple bar both ways. Spray it with sealer from outside the slab. Job done, cut joints next day. It's the consistency of runny porridge. Ive never had any big dips or uneven areas in it.