MY 01 748, bought new.
Rockers first examined at 38400 miles.
1 opening rocker replaced; remainder all fine.
Oil used: Motul 300V fully-synth 15/50.
Earlier in it's life oil was only changed at stock 6000 mile intervals (and didn't seem to do to much harm TBH). However, have increased oil-changes to 3000 miles now the old girl's got a few miles under her belt! :P