That saying is a bit misleading. It's not high performance engines that need high octane fuel, it's high compression engines. Most all high performance engines are high compression, but not vice versa. Hence a dinky 1.8L turbo putting out 170HP is high compression, without the performance.
With a compression ratio of 10.2 on the 330, (10.5 on the 325) it's pretty high and should be fed gas with a high octane rating. However, the engine is self adjusting so little to no damage should be result from using low octane gas; though constantly reving your engine may prove otherwise.