After a bit more benchmarking and comparisons on the web, and considering a bunch of average scoring machines, I have determined that [b:0d676f5f87]Photoshop 7[/b:0d676f5f87] performance With PearPC and Panther on my Windows XP host, running either PearPC .3.1 or a .4pre build gives roughly the same performance as a G3 266 - G3 300 running OS X.
So far, using [i:0d676f5f87]Photoshop 7[/i:0d676f5f87], I see:
a [b:0d676f5f87]20X[/b:0d676f5f87] slowdown over the host machine.
a rough equivalent of a [b:0d676f5f87]G3 266-300[/b:0d676f5f87] with at least 512MB ram running OS X.x.x
a [b:0d676f5f87]4X[/b:0d676f5f87] slowdown compared to the [i:0d676f5f87]stated CPU speed[/i:0d676f5f87] shown in OS X's System Profiler.
My experience with Altivec builds has been spotty at best, with some apps failing to even run. I have limited my tests to the non-altivec builds. The exception has been XBench, which liked the Altivec build and showed a considerable performance increase.
With XBench, I see roughly a [b:0d676f5f87]4.5X[/b:0d676f5f87] slowdown over the [i:0d676f5f87]stated CPU speed[/i:0d676f5f87] in the System profiler when running an Altivec build, and a [b:0d676f5f87]8X to 9X[/b:0d676f5f87] slowdown when running a non-Altivec build. That's [i:0d676f5f87]very[/i:0d676f5f87] approximate.
I don't know if Xbench is a practical benchmark for comparison because of the huge variability in posted scores among the same model macintoshes. It is also not cross-platform, so I cannot relate its results to the host machine.
Bryce 5 shows a consistent slowdown over the host of about [b:0d676f5f87]19X [/b:0d676f5f87]to [b:0d676f5f87]20X[/b:0d676f5f87], Altivec build or not.
Strata3D CX (demo) is impractical to use as a benchmark at this point because the render time of the test images available to me take a very long time (over ten hours), and the application itself has taken over an hour just to load! Maybe some wierd Altivec thing causes this, as I had a similar experience with Quark and Photoshop.