Just my observation, but if you get a booger with auto primer you have a booger. If your using tamiya, don't panic and leave it sit and when you come back the next day it will be smooth as silk no blemish at all. More costly yes but a very good product. I used to use plasti-coat t-235 but they have had to of changed the formula. It seems way thicker and squirts alot more no matter which nozzle you use. Longer dry times it just seems like a different product. I only know of 2 places that still carry it around here everyone else switched. Never had a problem going back or forth between auto and tamiya maybe ive been lucky.