Here's a quick summary of the 4 people that posted actual results in the last 2 pages of this thread.  

Suprnova | 3600 sol/s | .205 ZCL per 24 hours | 0.000057 ZCL per sol in 24 hours | Shitnoff
MPH | 5300 sol/s | .275 ZCL per 24 hours | 0.000052 ZCL per sol in 24 hours | MrTDHP
MPH | 4800 sol/s | .226 ZCL per 24 hours | 0.000047 ZCL per sol in 24 hours | dempsey1200
MPH | 25000 sol/s | 1.50 ZCL per 24 hours | 0.000060 ZCL per sol in 24 hours | amalkey

Obviously, this isn't enough data to come to any meaningful conclusions but there's quite a disparity in efficiency.  The only thing I can think of is using different mining programs and maybe timing of some block awards.  I might try out Suprnova pretty soon.