Ive got a set of pressed metal plates from DTUK, search it on the forum, They look awesome, especially with LED numberplate lights on the rear. they were about £30 iirc.
I was very reluctant to buy them because i didnt want to be stopped every 5 minutes, but i got them, and i actually had police tail me all the way through Cardiff for at least 15 minutes the other day, and they didnt stop me. Had them follow me loads, must be the stereotype with S3 and dealers or something... but no, never been stopped, yet...