Hi, I have searched for an up to date review on Oloneo photoengine without success so far.
I cannot make up my mind between Oloneo photoengine and Photomatix pro 4.
To add to the possible choices, have you considered SNS-HDR? I know it's an application for the Windows OS platform, but it reportedly also runs under Parallels or Fusion on a Mac, in case that is what you use.
I've been following the developments in HDR and exposure fusion for many years already, and SNS-HDR
is IMHO hard to beat in its natural (and halo free) tonemapping of huge dynamic range images. It even gets better with each update, just when you think that it is hard to improve any further. Recommended, and relatively affordable.