Are they a member of Detailing World? Would be interested to see some of their work
+1. I get most of my detailing advice from a very well known and respected detailer. He's generally the most expensive in the UK and he can charge that for a reason.
As I say, each to their own. I don't understand your process of sealing before polishing so I'll stick to mine. It seems to work so I'll stick to it!