So far everything's seems to work well without any performance lag. However I noticed the screen saver didn't work as expected.
Under Snow Leopard I set the Screensaver to play photos from a selected folder in iPhoto and this led to a nice slide show when the Mac was idle.
This setting didn't carry over to Mavericks, in fact no iPhoto folders were seen in the Source drop-down menu! Checking the forums, there were recommendations from upgrading to iLife'11 to running a Terminal command.
However not wishing to spend more money on this upgrade, I experimented with linking Screensaver with an alias of an iPhoto folder. It wasn't elegant but it worked!
- Goto Home > Pictures
- iPhoto Library
- Ctrl-click > Show package contents
- Choose a folder within Modified > File > Make alias
- Drag alias to Pictures Folder
- System Folder > Screensaver > Select type of slide show > Source
- Choose Folder... > navigate to Pictures Folder and select the alias.
- Thumbnail of the slideshow will be displayed and closing the System Folder will activate the slideshow when the Mac is idle.