the stuff from B&Q is £25 for 5ltrs (maybe 4ltrs) - a heck of a lot cheaper than protectacote - looks better too, is chemical resistant, water proof all the rest etc etc.
add to that its much easier got, easier to apply, lasts longer, looks better - why waste your time and money with protectacote - I had protectacote on the van before and it was rubbish.