I've only tried ViewIt for 2 hours, but already found 3 things I do not like:

1. ViewIt's (VI's) Help page says "For better efficiency place ViewIt in your dock." Well that's still not efficient because dragging a folder of images onto the icon does NOT open VI! Even when VI is already open, you can't drag a folder onto the icon, you must drag it into VI's window. So by adding VI to your Dock, all you're doing is making it a bit faster to open the app.
I set VI to open in fullscreen mode, so I could view my images in fullscreen (makes sense, no?). I thought I could drag a folder onto the icon in the Dock and poof--fullscreen images would appear. But nooooo, I have to first open VI. So when I opened VI, it opened in fullscreen mode, meaning I could no longer see the Finder where the images folder was, nor could I access the dock. I had to hit Escape, to minimize ViewIt's window, THEN drag the folder into VI's window, THEN click the fullscreen button to finally see them in fullscreen. That is NOT convenient, that is d@mn INconvenient!!!

2. There is NO delete button to delete unwanted images from a folder. You can use a key COMBO to delete a file, but this means I have to take my hand off the mouse, press ⌘+Delete and then move my hand back to the mouse. Alternatively you can right-click and scroll through the contextual menu. I'm supposed to do this for EVERY item I want to delete?! NO WAY-I want ONE button!
After de-selecting a default preference, you CAN drag images to the trash IF you aren't in fullscreen mode but that's sloooow if you have Dock-hiding enabled as I do.
If I'm sorting a folder of 200 images, I should be able to click one button to quickly move that item to Trash while I advance to the next image. There would also HAVE to be an Undo command for this, to undelete the last deleted item.
The lack of a delete key blows this software for me. The developer may have intentionally left it out as a safety feature, but I see a delete button as a vital feature.
3. VI quits a LOT. I was trying to experiment with several functions in the Tools menu, but VI kept quitting and I never knew why. For example, in the regular window, whether looking at a single image or thumbnails, every time I clicked Tools→JPEG Apply Lossless Rotations, VI Quit. If I selected Tools→Rename Sequentially, then clicked Cancel, VI quit.


iBook G4 1.33, 1.25GB RAM,