I haven't used the ones from that seller so I can't speak for them. Looks like they only ship to Canada.
I used some several years ago for the RR and they turned out great. Fairly easy to do. I probably spent a couple hours one day and a couple hours the next. I think the company I bought them from was Performance Graphics. Picked them up at the Mopar Nats. There's also companies out there now that will actually screen print them on as well.
Dave