Yes, always a worry when it comes to a varnish, which is why I now always do by hand. Will never look at another aerosol. Had one go cloudy on me, nearly cried with rage and frustration. Also lightly sprayed a newly finished army with white...yes picked up the wrong aerosol. I am deeply scarred!
I know what you mean. I've been dipping for years now, but I still have that moment of hesitation every time. I just dipped 30 figures this evening, but I had to psych myself up for it.