My frame was 5017 the first time I had it powder coated. It was no where near factory. It looked so bad I contacted the powdercoater and the supplier. The supplier sent more 5017 to the powdercoater and a bunch of samples to me. In the end my frame, the new test panel and the sample from the supplier all matched. I ended up having the frame blasted and powder coated a second time with 5010.
My advice it to get some samples from the powder coat shop and do some comparisons before you commit to a color. Then go with what you like. There is a reason they make a gazillion different PC colors... we all have different preferences.
You can get a good idea of the differences by looking at the Picasa album linked in my signature.