I've got my plugs to a stage I'm happy with and I'm about to start on the mould making. I've chosen the unimould system from easy composites. This will be my first time.

I am in a similar boat to you Shinobiwan, I can't spray 2K. I use 1K stuff to paint all my plugs, and they come out fine using PVA. I have destroyed a couple unfortunately, but that was before I started spraying the PVA. I don't necessarily count coats, but what I normally do is spray a few (2 or 3) very fine mist coats, then I go over it with heavier coats as if I were spraying a paint. So by the time I' done, I will probably have done 2-3 mist coats, and then 2-3 heavier coats. If your PVA is anything like mine, it won't look perfectly flat at first, it will have some tiny air bubbles in it. But these all disappear after 5-10 minutes, and leave a very smooth surface. Spraying it on this heavy will make it pool in tight corners and radius' though, so have some paper towel handy and just stick a corner into the pools and let it soak up. Or use it more sparingly in the corners. It will also take a little longer to dry, which you can speed up with a hair dryer or a heat gun, but just be careful not to cause bubbling with the heat as that will come out in your mould.