I would stay clear of the master airbrush if possible, they do tend to be of poorer quality. However occasionally you do get a good one but thats if your very lucky. I would look for some % off coupons rom HobbyLobby or Michaels and try to get an eclipse or something similar. I know theyre more expensive BUT almost guaranteed quality and issue free spraying. other places may have them cheaper, this needs to be researched first.
The grex g-mac is expensive but is super quality, i've had mine for over 10 years no issues, and the mac valve is very good. Chinese ones are almost on or off.. If you have the budget, get one even if you don't use the mac valve part at the moment, you may find you want to use it later on in your airbrush journey.
Lee