Hey Frank (doitwright),
You asked the question, so I will throw my 2 cents in.
The taped approach yields a very clean look, cleaner than factory, if done properly.
Therefore I went with the two silicone rubber type stencils to give a more factory finish with some fuzzy edges.
I really took my time and cleaned the stencils between coats. I did not want to put down the stencil on a hubcap if it had paint on it.
I used single stage paint in a rattle can from paintscratch.com (I'm not affiliated with them in any way).
The match in color was perfect or near perfect and considering the hub cap is separated from any painted surface with a huge black circle (the tire) you cannot see any difference in finish.
After completing the caps, it looked like I needed to do two of them over again, ..... but once they are on the car you really don't see any imperfections. You know how people talk about cars as being a "10 footer"? Well my hubcaps are a 3 footer.
Take care,
Mark