Sorry if this is covered in a mega thread. I'm looking for a late production powerbook G4 to run the last supported Lightroom/Aperture and photoshop just for demoing but it still needs to be 'useable'. Looking at the spec table they all seem pretty similar spec from the 12in to the 17in. I would max out the memory and install a SSD but am I really going to notice a huge difference between a 12in 1.5ghz/1.25GB and 17in 1.67ghz/2GB when running these apps?