Vallejo's formula is nowhere near that of Tamiya's (not sure about MM). Tamiya 'acrylics' are ether based, not water based as Vallejo.

If you're getting tip dry or pebbled surface, you're spray at too high a pressure. The only time I remember getting tip dry was with Tamiya since the ether evaporates faster than water. Model color when brushed dry pretty quick, but properly thinned you shouldn't have an issue.

I'm not knocking Tamiya's paints, they're excellent, or trying to sell you on Vallejo by mentioning that, you just need different AB practices for different paints. I use Vallejo exclusively for the last 10 years or so. My kids airbrush and there's no need to expose them to the solvents in Tamiya. That sweet candy smell comes at a price.