I've been learning with the Createx Auto Air and Createx Wicked Colors. Note, I haven't used them over the Rusto filler primer (yet) but I have used the Createx Auto Air Sealer White. Generally speaking, I haven't found the acrylics to go on too thin. I did have an issue this weekend with the Pearl white (see my Aerobee 150 build thread in the LPR forum)... I got bleed through of some pen marks. Should have covered with an opaque white first.
Other than that, no problems. IT does take several coats to get full coverage and depth, but that's no big deal. The stuff dries quickly and no fumes to bug my wife! I like painting inside instead of in a cold/dusty/sometimes hellishly hot garage. I paint in the basement; it's always in the 60's in there--with no excess humidity blush problems!
The best of both worlds would be to use the filler primer, sand, then cover with acrylic from there. I haven't recently tried the rusto filler primer in a cold garage; I've assumed it would take a while to dry. Last winter I did a test and it was still stinky after several days.
I went to water based acrylics (with a Paasche H single action external mix brush from Hobby Lobby, driven by a 20 lb CO2 tank instead of noisy compressor) so I could paint through the cold winter and not have any fume issues. See this thread:
Water-based acrylics: looking for a quickstart for rocketry
So far I find the paints to work well, I can use either Future, or Liquitex high gloss varnish, or even (in the garage) Valspar lacquer clear over them, depending on what I can achieve.
The only thing I haven't found is a good water based sandable primer!
Marc