I exclusively use Cover Flow now and love it. Why pointlessly cripple yourself with only a textual view when you can have split screen visual and textual? Quick Look is a great little tool and I use it for pictures, Office documents, PDFs, you name it.
I could see if you had a smaller screen or older, slower machine perhaps it wouldn't run as well, but I have absolutely no issues with my nice new 24" 2.4 GHz iMac with 4 GB of RAM.
I could see if you had a smaller screen or older, slower machine perhaps it wouldn't run as well, but I have absolutely no issues with my nice new 24" 2.4 GHz iMac with 4 GB of RAM.