I've worked with GE, AB and the WinCPU from Automation Direct and by far I prefer AB.
GE has potential with Proficy Machine Edition, however the ladder editor is very poor in my opinion. It's still structured like the original dos based programming software Logic Master 90, the advantage is that old PLC projects can be converted to PME, but graphicly and usability is just not nearly as nice as what you see in AB.
The WinCPU uses flowchart (viso) based programming, very different mindset...after I got into it I it made sense, however to me it doesn't make sense to use a cpu who's programming language doesn't resemble anything that is currently in the industry. Sure you'll save money on hardware, but you lose money due to efficiency loss.