Matcap Matcap is offline

Definitely spray, but you have to do it with a can that you are confident is aerating well, and that the paint isn't coagulating within. Then, make sure you vary the distance of nozzle to model, going up at the points where you want a lighter coat... so pretty much all of the white. I practiced on a big cardboard box a few times to get the effect that I was after.

I also get that grainy-ness with GW white and army painter of all colours. It is really annoying but it seems to be preventable with enough 'ablative' spraying on cardboard or similar and shaking the can, holding upside down and spraying to clear the nozzle.

Hey! The 'clean coat' on that Thunderbolt is not so clean out of the photo, but I did it by undercoating the top white and the underside black, washing the whole top with watered down white to get a smoother layer, wishing dearly that I had an airbrush to get a wet blend effect around the engines, and then highlighting with a thick white paint on every edge on top of the aircraft. It was only as bad as it sounds doing the top highlights - the bottom was super fun and the evening out of the white wasn't too bad.