PU Lacquer on alloys

[blackchim]

Re-finishing my imola alloys, just finished primer before silver. I have a can of PU Lacquer to finish, and reading the directions its says to get the correct finish I need to rub down the new paint surface to get a matt finish using wet 1200 paper. Is this necessary ie how much difference does it make?

Whats the experience out there?

Thanks