Its good gear for protecting against water leakage and seam seepage and its grippy under foot, make sure the van floors clean and keyed up properly before application.
I did a mates Transit that he used to use for valeting and it was an easy enough job after keying the floor up I wiped it down with some panel wipe and just rollered it on (use a small brush into the corners).
I gave that 2 coats (but if I had been paying it would only have got one) finishing it about 2 inches up the sides of the van so water couldnt get down into the seams between the floor and sill.
Its pretty potent smelling stuff so a respirator is the best way to go and leave the doors open for ventilation.
I put on the first coat late in the afternoon then left it overnight with a small electric heater going in the workshop then left outside all the next day and repeated the next evening, it stank a bit for a couple of days but it lasts well and still looked good the last time I saw it a few months ago.