Desktoptopia
So recently I was looking for desktop backgrounds to fit my monitor, I wanted a source where there would be lots of wallpapers available. I needed a source which had premium wallpapers which looked decent. Whilst I was searching I came across desktoptopia a free Mac and Windows client which changes your desktop automatically. You can set how often you want it changing. 
There are no resolution issues as most backgrounds fit the larger monitors 24″<
For usability I would say it’s very easy, you just open the settings up and select when you want it changing, if you want it to start up and loads of other settings which I love. Gives you full control! You can even select which categories you get the images from to make sure you get ones that suit your style.
For performance I would say it stacks up well. There might be slight problems whilst your computer changes the image if you have an older pc but that’s not strictly there fault.
For design its good enough, it doesn’t need to look great as it’s a background program. It has a good layout to ensure it’s easy to change you’re settings on the fly.
The quality of the backgrounds I have experienced so far are brilliant. There is lots of verity and all of the images are of designer quality.
To download the software go to desktoptopia.com.
As always if you have a question write a comment. To contact me direct send me a message by email