Just to add my experience with Krylon primers:
I found that their Dual Paint + Primer series is good, but only if you get the Flat version (not Satin or Glossy).
I started out with the Satin, and the bones minis that I primed stayed tacky for a very long time (it took about a month for the tackiness to go away). After switching to Flat, I've haven't been having any issues with tackiness.
According to their website, Krylon only makes Flat in black and white (in their Dual Paint + Primer series anyways)
Also, if it matters, I live in Canada and I try to spray indoors (in my garage) so that the air isn't too cold when I am spraying. I don't think that has affected my results, but I thought I'd mention it.
Happy painting, everyone!