I have used the GW primer for a long time, and it does a good job, but is super expensive, and now they are using a new spray nozzle which I have had problems with. I always have to buy black. Twice I have bought white, but it has never seemed to stick to the figures for me.
So, with all of that in mind, I have been looking for a new primer. I checked out comments over at The Miniatures Page and have decided to test a few products that people there use.
There are three types that I am trying. The first is Colorplace Gray Primer (Walmart Brand). I bought for $1.25. The second is Krylon Primer (I like the fact that they have multiple colors of primer). I bought this for $2.95. The final is ColorPlace Flat Black Paint, which costs $.95.
I then took all three choices and shook them up and sprayed some figs. I have to say that all three sprays went on easily with a nice smooth spray. All three went on with light coats that did not obscure the details. The Krylon went on the heaviest, and it might be enough to cause some detail loss on smaller scale figs. I tried it with some 10mm figs, and didn't notice any problems though.
Both of the ColorPlace sprays dried within minutes. The Krylon took about a half hour to dry adequately.
I then took the figures and rubbed them with my fingers. The ColorPlace Gray Primer had a little of the primer rub off after a little bit, but all held pretty well. The Krylon held the best, but the ColorPlace Flat black was right behind it with barely noticeable loss.
I then put on a quick coat of one color to see how well it stuck. The two ColorPlace paints took the paint very well. (I use Vallejo Paints). In this example, the Krylon also did very well, but when I painted some 15mm figs, there was just a small amount of beading to this primer which made painting on it a little more difficult.
All three primers did very well, and were at least as good as any GW primer that I have had. (if not better). The Krylon had the best adhesion, but was a little difficult to work with. I think that my choice will be the ColorPlace Flat Black paint. At $.97 for a can, the price can't be beat!