I decant Tamiya, and everything else, directly into bottles like tis. If you want to leave sit overnight it allows the gas out and minimizes evaporation since it is already at the right consistency. The process can be sped up easily by closet the spout , shaking and resealing the pressure. Do that few times' til it goes flat. Like getting the fizz out of a bottle of soda.
I order these about a couple of hundred at a time either 1 or 1.5 oz.. That last a loooong time too. The other thing they are great from is when you have a project that will need a large amount of paint. This way you can get the consistency, and color if you are mixing, you need for a bath big enough to do the whole job and not worry about mixing a 2nd batch tat might be different.