What I was looking for, but with a catch

Is actually a good alternative to QuickRes and is available on the AppStore. The only catch is that doesnt have available the 1920x1200 mode, identified on the retina as the "More Space" display resolution.

On my MacBook Pro 15" Retina gives the following available resolutions:

4:3 800x600
4:3 1024x768
16:10 720x450 HiDPI
16:10 840x525 HiDPI
16:10 1024x640 HiDPI
16:10 1280x800
16:10 1280x800 HiDPI
16:10 1440x900
16:10 1680x1050
16:10 2048x1280
16:10 2560x1600
16:10 2880x1800

I will deinstall it and get back to QuickRes, hopefully the 1920x1200 resolution mode will made available soon.

mbmobile about Display Menu, v1.0