I've also included results of memory bandwidth tests using Newer Tech's GaugePro. Remember the most important results are on the next page of the review which covers real world applications and game performance.
Benchmarks have their place, but actual applications performance is what really matters.
As you'll see in the Photoshop 5.5 test results, until benchmarks like MacBench take advantage of Altivec, they are not an indicator of what the G4 is potentially capable of. However, MacBench CPU scores seem to be a pretty accurate gauge of G4 performance in applications that don't use Altivec instructions. Be aware that Macbench Graphics scores will vary depending on graphics mode and the installed video card. The graph below compares my rev A iMac before and after the upgrade. My MacBench CPU score was slightly lower than Newer's 1380 noted in their press release.