My pleasure.
Been doing a lot of playing with Aperture since I sprang for an SSD. Doing different things and watching the Activity Monitor I notice:
-- First pull of any image takes about 1-2 seconds. (I currently have large, quality 8 previews.)
-- Zooming to full res can take another 2-3 seconds. This is for a 10 MP NEF on a dedicated drive. a 100 MB TIFF takes a bit longer.
-- These speeds are largely constant, whether everything is on the SSD or on a conventional HD.
-- Scrolling 11,000 images in the browser takes less than 1 second per screen. Maybe a bit faster with the SSD. ALWAYS faster the second time. (Logical, given the way OSX and, by extension, Aperture caches. This is probably the reason that purging the caches helps; there is probably a lot of Aperture 2 routine still stuck in there.)
-- Brushing and sharpening a 100 MB file will get all of the CPU's engaged. These processes will also generate lots of HD reads and writes. Again, logical, as you are editing the Version file and then demanding that the GPU refresh the screen. There is usually a lagging "Loading" message (and a "Processing" message in the Aperture Activity Monitor. Again, logical when you consider how Aperture works. Surprisingly, running on the SSD does not make that great a difference.
-- RAM makes more difference than anything else. Paging is about the slowest thing you will encounter. In my case (and I usually have Safari and Mail open when I am using Aperture), going from 13 GB of RAM to 21 GB reduced paging to zero. At this point, I could see that things like brushing were limited only by the actual speed of the CPU.
-- Putting Aperture, the Library, and even some of the Masters on the SSD made much less difference than I would have expected. Again, tribute to OSX's effecive caching and a lot of RAM. With less RAM, and more paging, then the SSD would probably be a bigger speed boost. That said, the SSD is very nice for speed of boot, reboot, application loading, and other things. It is just not the panacea for Aperture speed that RAM is.
As always, YMMV. 😉