I have had my twinjector from Basstackle for many years now. Takes practice and as Justin said, temps being close.
For production, there is no way you can get close the amount of baits doing them with a laminate plate or insert. If they are just for you, you might not care about all the extra time.
Just remember, darker colors will be hotter if you heat it the same amount as a white or light color. Colors with flake will be hotter. Heat those slightly shorter amounts or the lighter color just a little longer. As Justin said, temperature matters.
Not sure what temp I inject at but sure it is cooler than most. Super hot plastic will swirl the colors much easier than cooler stuff.
Learn the twinjector and you can shoot near perfect laminate every single time. And get them done FAST.
Jim